Cobalt availability in the soil plant and animal food chain: a study under a peri-urban environment.

Cobalt metal is considered as an essential trace element for the animals. Present investigation was undertaken in the peri-urban area to analyze the cobalt availability in animal food chain by using different indices. Cow, buffalo and sheep samples along with forage and soil samples were collected from the three different sites of District Jhang and analyzed through atomic absorption spectrophotometer. Cobalt values differed in soil samples as 0.315-0.535 mg/kg, forages as 0.127-0.333 mg/kg and animal samples as 0.364-0.504 mg/kg. Analyzed cobalt concentration in soil, forage and animal samples was found to be deficient in concentration with respect to standard limits. Soil showed the minimum cobalt level in Z. mays while maximum concentration was examined in the forage C. decidua samples. All indices examined in this study has values lesser than 1, representing the safer limits of the cobalt concentration in these samples. Enrichment factor (0.071-0.161 mg/kg) showed the highly deficient amount of cobalt enrichment in this area. Bio-concentration factor (0.392-0.883) and pollution load index (0.035-0.059 mg/kg) values were also lesser than 1 explains that plant and soil samples are not contaminated with cobalt metal. The daily intake and health risk index ranged from 0.00019-0.00064 mg/kg/day and 0.0044-0.0150 mg/kg/day respectively. Among the animals, cobalt availability was maximum (0.0150 mg/kg/day) in the buffaloes that grazed on the C. decidua fodder. Results of this study concluded that cobalt containing fertilizers must be applied on the soil and forages. Animal feed derived from the cobalt containing supplements are supplied to the animals, to fulfill the nutritional requirements of livestock.

Modern management of a patent foramen ovale.

A patent foramen ovale (PFO) has been associated with medical conditions such as cryptogenic stroke, migraine with aura, and decompression illness. Whether closure of the PFO has clinical benefit has been suggested from registry studies, but not yet confirmed in multiple randomized trials. Methods of diagnosis of a PFO and a summary of the current evidence for treatment is presented and discussed as a guide to patient-centred decision-making.

Metformin: safety in cardiac patients.

Metformin is a biguanide, insulin sensitiser that reduces blood sugar levels. There are concerns about the risk of lactic acidosis in patients receiving metformin who have procedures requiring iodinated contrast, and in those with renal impairment or heart failure. The data on which these concerns are based are reviewed, with the conclusion that metformin treatment is rarely to blame for lactic acidosis. A generic policy of stopping metformin 48 h before and 48 h after the procedure in all patients is counterintuitive, lacks any evidence base and does not conform to the principles of best practice. In patients with heart failure, although the underlying condition can predispose to lactic acidosis, existing evidence suggests that metformin use is associated with improved outcome rather than increased risk.

Metformin: safety in cardiac patients.

Metformin is a biguanide, insulin sensitiser that reduces blood sugar levels. There are concerns about the risk of lactic acidosis in patients receiving metformin who have procedures requiring iodinated contrast, and in those with renal impairment or heart failure. The data on which these concerns are based are reviewed, with the conclusion that metformin treatment is rarely to blame for lactic acidosis. A generic policy of stopping metformin 48 h before and 48 h after the procedure in all patients is counterintuitive, lacks any evidence base and does not conform to the principles of best practice. In patients with heart failure, although the underlying condition can predispose to lactic acidosis, existing evidence suggests that metformin use is associated with improved outcome rather than increased risk.

The Coronary Artery Revascularisation in Diabetes (CARDia) trial: background, aims, and design.

BACKGROUND: Patients with diabetes have an increased incidence and severity of ischemic heart disease, which leads to an increased requirement for coronary revascularization. Comparative information regarding mode of revascularization--coronary artery bypass graft surgery surgery (CABG) or percutaneous coronary intervention (PCI)--is limited, mainly confined to a subanalysis of the Bypass Angioplasty Revascularization (BARI) trial, suggesting a mortality benefit of CABG over PCI. No prospective trial has specifically compared these modes of revascularization in patients with diabetes. OBJECTIVE: The Coronary Artery Revascularisation in Diabetes (CARDia) trial is designed to address the hypothesis that optimal PCI is not inferior to modern CABG as a revascularization strategy for diabetics with multivessel or complex single-vessel coronary disease. The primary end point is a composite of death, nonfatal myocardial infarction, and cerebrovascular accident at 1 year. METHOD: A total of 600 patients with diabetes are to be randomized to either PCI or CABG, with few protocol restrictions on operative techniques or use of new technology. This gives a power of 80% to detect non-inferiority of PCI assuming that the PCI 1-year event rate is 9%. A cardiac surgeon and a cardiologist must agree that a patient is suitable for revascularization by either technique prior to recruitment into the study. Twenty-one centers in the United Kingdom and Ireland are recruiting patients. Data on cost effectiveness, quality of life, and neurocognitive function are being collected. Long-term (3-5 year) follow-up data will also be collected.

Distinct yet complementary mechanisms of heparin and glycoprotein IIb/IIIa inhibitors on platelet activation and aggregation: implications for restenosis during percutaneous coronary intervention.

OBJECTIVE: To study the effect of unfractionated heparin (UFH) versus low molecular weight heparin (LMWH) in combination with glycoprotein (Gp) IIb/IIIa blockers on platelet activation and aggregation. METHODS: Washed platelets were stimulated with thrombin in the presence or absence of UFH (monoparin), LMWH (enoxaparin), and a Gp IIb/IIIa blocker (abciximab, eptifibatide, or tirofiban). RESULTS: Although Gp IIb/IIIa antagonists blocked the final common pathway of thrombin induced platelet aggregation, UFH and LMWH were better at blocking upstream platelet activation. UFH was significantly more effective than LMWH at inhibiting P selectin expression (p = 0.001) and platelet derived growth factor release from thrombin activated platelets (p = 0.012). CONCLUSIONS: UFH and LMWH exert complementary effects to Gp IIb/IIIa blockers by inhibiting afferent pathways of platelet activation. Coadministration of heparin with Gp IIb/IIIa blockers provides improved protection against persistent platelet activation, thereby improving outcome after percutaneous coronary intervention. Judging from these data, UFH may be more effective in this regard than LMWH, at least in vitro. The use of LMWH in preference to UFH during percutaneous coronary intervention, although initially attractive, may inadequately protect against platelet activation despite the presence of Gp IIb/IIIa blockers.

Takayasu's arteritis: management of left main stem stenosis.

Takayasu arteritis is a chronic vasculitis involving the aorta and its main branches, the pulmonary arteries, and the coronary tree, and needs to be considered in a young patient with angina, in particular when pulses are absent. This case illustrates the limitations of exercise testing in diagnosing the extent of coronary artery disease and the risks associated with coronary angiography in patients with inflammatory disease in the left main stem coronary artery. It also highlights the novel use of non-invasive scanning with positron emission tomography using 18-fluorodeoxyglucose in assessing remission from this disease. Revascularisation was performed with percutaneous transluminal coronary angioplasty and stenting as an emergency procedure, but treatment of the restenosis with directional atherectomy was based on a review of the available literature. The lymphocytic alveolitis seen in this patient has not been previously described in Takayasu's disease.

Association of maternal endothelial dysfunction with preeclampsia.

CONTEXT: Preeclampsia is believed to result from release of placental factors that damage maternal vascular endothelium. However, because most studies have been conducted during pregnancy, it has not been possible to separate maternal from placental mechanisms underlying endothelial dysfunction in preeclampsia. OBJECTIVE: To determine whether endothelial function is impaired in nonpregnant women with previous preeclampsia and whether endothelial dysfunction is mediated by oxidative stress. DESIGN AND SETTING: Case-control study conducted at 3 hospital maternity units in London, England, between July 1997 and June 2000. PARTICIPANTS: A total of 113 women with previous preeclampsia (n = 35 with recurrent episodes; n = 78 with a single episode) and 48 women with previous uncomplicated pregnancies, all of whom were at least 3 months (median, 3 years) postpartum. MAIN OUTCOME MEASURES: Brachial artery flow-mediated (endothelium-dependent) and glyceryl trinitrate-induced (endothelium-independent) dilatation were compared between previously preeclamptic women and controls. To investigate oxidative stress, these measurements were repeated after administration of ascorbic acid, 1 g intravenously, in 15 cases and 15 controls. RESULTS: Mean (SD) flow-mediated dilatation was lower in women with previous preeclampsia compared with controls (recurrent group, 0.9% [4.1%]; single-episode group, 2.7% [3.5%]; and control group, 4.7% [4.3%]; P<.001). In contrast, glyceryl trinitrate-induced dilatation was similar in the 3 groups (recurrent, 19.5% [5.9%]; single-episode, 21.0% [8.0%]; and control, 21.0% [8.3%]; P =.65). Impaired flow-mediated dilatation in previously preeclamptic women was not accounted for by recognized vascular risk factors. Ascorbic acid administration increased flow-mediated dilatation in previously preeclamptic women (baseline, 2.6% [3.3%]; after administration, 5.6% [3.0%]; P =.001) but not in controls (baseline, 6.2% [3.3%]; after administration, 6.7% [5.0%]; P =.72). CONCLUSIONS: Our results indicate that endothelial function is impaired in women with previous preeclampsia and is not explained by established maternal risk factors but is reversed by antioxidant ascorbic acid administration.

Cost effectiveness of ramipril treatment for cardiovascular risk reduction.

OBJECTIVE: To assess the cost effectiveness of ramipril treatment in patients at low, medium, and high risk of cardiovascular death. DESIGN: Population based cost effectiveness analysis from the perspective of the health care provider in the UK. Effectiveness was modelled using data from the HOPE (heart outcome prevention evaluation) trial. The life table method was used to predict mortality in a medium risk cohort, as in the HOPE trial (2.44% annual mortality), and in low and high risk groups (1% and 4.5% annual mortality, respectively). SETTING: UK population using 1998 government actuary department data. MAIN OUTCOME MEASURE: Cost per life year gained at five years and lifetime treatment with ramipril. RESULTS: Cost effectiveness was pound36 600, pound13 600, and pound4000 per life year gained at five years and pound5300, pound1900, and pound100 per life year gained at 20 years (lifetime treatment) in low, medium, and high risk groups, respectively. Cost effectiveness at 20 years remained well below that of haemodialysis ( pound25 000 per life year gained) over a range of potential drug costs and savings. Treatment of the HOPE population would cost the UK National Health Service (NHS) an additional pound360 million but would prevent 12 000 deaths per annum. CONCLUSIONS: Ramipril is cost effective treatment for cardiovascular risk reduction in patients at medium, high, and low pretreatment risk, with a cost effectiveness comparable with the use of statins. Implementation of ramipril treatment in a medium risk population would result in a major reduction in cardiovascular deaths but would increase annual NHS spending by pound360 million.