Enhancing beneficial antioxidants in fruits: a plant physiological perspective.

The aim of this review is to present an outline of the physiological perspectives of beneficial antioxidant production in fruit. The drive to enhance the consumption of fruit and vegetables in the human diet is linked with positive effects of beneficial antioxidants impacting on health promotion. We briefly outline our physiological understanding of environmental processes which induce the production of reactive oxygen species and how antioxidants prevent plant cellular damage. More specifically, we describe the impact that environmental stresses, such as drought and radiation, have on the production of endogenous antioxidants and how these stresses can be incorporated into novel experimental crop growing systems to achieve high antioxidant concentrations in fruits. This includes in particular the use of irrigation application techniques and enhanced light reflectance to increase the concentrations of bioactive compounds such as ellagic acid and ascorbic acid.

Transmitral Doppler assessment of left ventricular diastolic function during coronary artery bypass surgery.

OBJECTIVE: To evaluate which Doppler transmitral velocity indices of left ventricular diastolic function change with alteration of left ventricular filling pressure. METHODS: Twenty-two patients undergoing coronary artery bypass surgery. The effect of fluid loading on indices derived from the transmitral Doppler waveform, recorded by a trans-oesophageal echocardiography, was evaluated using a generalised linear statistical model. RESULTS: E-wave maximum velocity, E-wave acceleration time and slope, E-wave deceleration slope, A-wave maximum velocity and E/A wave maximum velocity ratio showed significant changes after alterations in left ventricular filling pressure. E-wave deceleration time and E-wave maximum velocity/time velocity integral showed no significant change after fluid loading. CONCLUSION: Several commonly used Doppler derived indices of left ventricular diastolic function are significantly affected by changes in filling pressure of the left ventricle. This may limit the usefulness of the Doppler method for serial assessment of diastolic function when the left ventricular filling pressure has changed between assessments. Only the E-wave deceleration time did not show significant changes and might be a useful Doppler index for the serial measurement of left ventricular compliance but this needs to be confirmed with haemodynamic measurements.

Is it safe to discharge patients from accident and emergency using a rapid point of care Triple Cardiac Marker test to rule out acute coronary syndrome in low to intermediate risk patients presenting with chest pain?

PURPOSE: To determine whether patients presenting with chest pain who are at low to intermediate risk for ACS can safely be discharged from Accident and Emergency using Triple Cardiac Marker [TCM] [CK-MB, myoglobin, troponin I] without increasing risk and cost effective use of coronary care facilities. METHODS: Retrospective review of consecutive patients presented to A&E between Dec 2003 and July 2004 was performed and these patients were prospectively followed for six months for future coronary events and hospital admissions. A total of 325 patients presented to A&E with chest pain that were at low to intermediate risk for ACS. Paired TCM and ECGs were performed 2 h apart and the results were used to determine whether hospital admission was required. Follow up data was collected from hospital records, hospital database, GPS and patient interviews. RESULTS: 325 consecutive patients [225 men, 100 women; aged 18-97 years, median-68 years] were included in the study. Paired TCM was negative in 100 patients [30%] and they were discharged from A&E. The re-admission rate for this group of patients was 1% with ACS and no deaths from cardiac cause at six months. 36 [11%] had single TCM negative and were sent home with 3% re-admission rate with ACS and no death at six months. Subgroup analysis shows sensitivity and specificity of 85.7% and 96.5% respectively for TCM to diagnose ACS in this setting. CONCLUSION: Almost one third of patients who presented with chest pain and low to intermediate probability of ACS were safely discharged from A&E following paired negative TCM. Six month re-admission rate with ACS in this group of patients was only 1% with no death. Therefore paired TCM can be used to safely discharge this group of patients. This marker has the potential to significantly reduce hospital admissions.

Effects of cultivar, fruit number and reflected photosynthetically active radiation on Fragaria x ananassa productivity and fruit ellagic acid and ascorbic acid concentrations.

BACKGROUND AND AIMS: A number of strawberry varieties were surveyed for their total ellagic acid concentration, and attempts were made to determine if ellagic acid and ascorbic acid concentrations of two strawberry cultivars could be increased by polythene reflective mulches. METHODS: After adjusting crop yields and cultivation using polythene mulches with two different PAR reflective capacities, field- and polytunnel-grown strawberries were analysed for ellagic acid and ascorbic acid concentrations by HPLC. Comparative measurements of yield and fruit quality were determined along with plant developmental changes. KEY RESULTS: Ellagic acid concentration varied widely with strawberry cultivar (60-341 microg g(-1) frozen weight), as did the ratio of conjugated ellagic acid : free ellagic acid. Also, there was significant year-to-year variation in total ellagic acid concentration with some cultivars. Mulches with different reflective capacities impacted on strawberry production; highly reflective mulches significantly increased growth and yield, the latter due to increases in fruit size and number. CONCLUSIONS: Highly reflective mulches significantly increased total concentrations of ellagic acid and ascorbic acid relative to control in fruit of different cultivars. The potential of agronomic practices to enhance the concentration and amounts of these important dietary bioactive compounds is discussed.

Delayed complications after myocardial contusion.

A 45 year old farmer was kicked in the chest by a horse. In the days following the injury episodic breathlessness developed and he was admitted to hospital with right ventricular failure and pulmonary emboli. Echocardiography showed global right ventricular dysfunction but a right ventricular mural thrombus, the likely source of the pulmonary emboli, was not seen. He gradually recovered after treatment with anticoagulant. One month later he presented with a further complication--complete atrioventricular dissociation--that required a dual chamber pacemaker implantation. This patient had few initial manifestations of right ventricular myocardial contusion and this case illustrates that such patients should be closely monitored for delayed complications.

Screening the aged in general practice.

We describe a comprehensive screening project in a general practice in which patients over the age of 65 were assessed both socially and medically. We conclude from our results that there was little treatable but previously undiagnosed illness within the community studied.

Vasoconstrictor peptides and cold intolerance in patients with stable angina pectoris.

BACKGROUND: The exact mechanism that explains the phenomenon of cold intolerance in patients with angina remains controversial. Although the response to the effects of a cold environment has been examined in these patients, their response to cold air inhalation has produced conflicting results. In addition, the possible role of vasoactive peptides in the pathophysiology has not been explored. OBJECTIVES: The aims of this study were to examine the response of patients with stable angina to the effects of cold air inhalation during exercise testing, and to investigate the possible role played by the vasoconstrictor peptides endothelin-1 (ET-1) and angiotensin-II (AT-II) in the pathophysiology. METHODS: In a randomised order, 12 men with stable angina, whose medication had been stopped, underwent two separate symptom limited treadmill exercise tests. At one visit the patients exercised while breathing room air and at the other visit they exercised while breathing cold air from a specially adapted freezer. Serial peripheral venous blood samples were taken for ET-1 and AT-II estimations during each visit. RESULTS: Cold air inhalation resulted in a significant reduction in the mean time to angina (232.7 (20.4) s v 274.1 (26.9) s, P = 0.04) and the mean total exercise time (299.5 (27.0) s v 350.3 (23.9) s, P = 0.008), but no significant change in the time to 1 mm ST depression (223.3 (29.0) s v 241.3 (29.2) s, P = 0.25). There was no significant difference between the rate-pressure products at the onset of angina (P = 0.13) and the time to 1 mm ST depression (P = 0.85), but at peak exercise the rate-pressure product was significantly lower in patients breathing cold air as opposed to room air (P = 0.049). There was an equivalent significant decrease in ET-1 concentrations at peak exercise compared with that at rest at both visits (room air 5.0 (0.7) pmol/l v 4.3 (0.7) pmol/l, P = 0.03; cold air 4.4 (0.6) pmol/l v 3.8 (0.5) pmol/l, P = 0.02). There was a significant increase in AT-II concentrations 10 min after peak exercise in patients breathing room air (39.2 (6.1) pmol/l v 32.1 (4.8) pmol/l, P = 0.01) which was not repeated during cold air inhalation (36.6 (3.4) pmol/l v 28.3 (3.4) pmol/l, P = 0.07). CONCLUSIONS: Cold air inhalation in patients with stable angina results in an earlier onset of angina and a reduction in exercise capacity. Both peripheral and central reflex mechanisms appear to contribute to the phenomenon of cold intolerance. Peripheral ET-1 and AT-II do not appear to play a significant role in the pathophysiology.