Evidence of large-scale chronic eutrophication in the Great Barrier Reef: quantification of chlorophyll a thresholds for sustaining coral reef communities.

Long-term monitoring data show that hard coral cover on the Great Barrier Reef (GBR) has reduced by >70 % over the past century. Although authorities and many marine scientists were in denial for many years, it is now widely accepted that this reduction is largely attributable to the chronic state of eutrophication that exists throughout most of the GBR. Some reefs in the far northern GBR where the annual mean chlorophyll a (Chl a) is in the lower range of the proposed Eutrophication Threshold Concentration for Chl a (~0.

The GALA trial: will it influence clinical practice?

The General Anesthesia vs. Local Anesthesia for Carotid Surgery (GALA) trial did not show a difference in 30-day postoperative stroke, myocardial infarction and death rates between patients undergoing carotid endarterectomy (CEA) under local vs. general anesthesia.

The antithrombotic effect of dextran-40 in man is due to enhanced fibrinolysis in vivo.

Background: Dextran-40 is effective in reducing postoperative Doppler-detectable embolization in patients undergoing carotid endarterectomy (CEA). Dextrans are thought to have antithrombotic and antiplatelet effects. The mode of action is unclear.

Treatment of asymptomatic carotid disease with stenting: con.

The landmark trials of the 1980s established a powerful precedent for demanding that "evidence" rather than "intuitive reasoning" should determine practice regarding management of patients with carotid disease. Accordingly, for our opponents to succeed in this debate, they must first demonstrate that there is little remaining confusion regarding the optimal management of asymptomatic carotid disease and then provide compelling evidence that it is now reasonable to offer carotid angioplasty with stenting without the protection of randomized trials. It is our contention that neither can be demonstrated and that the motion cannot be sustained.

Repair of ruptured abdominal aortic aneurysms by endovascular techniques.

Emergency EVR for ruptured AAA is now technically feasible, and several reports with small numbers have appeared in the literature from major centers suggesting that the results may be the same as or better than seen with open repair. The immediate priority is avoidance of over-resuscitation together with the rapid transfer of the patient to CT and then to the operating theater. Because of the learning curve involved, these cases should be attempted only by major centers that have extensive elective endovascular experience.

Reevaluation of ENCORE: support for the eutrophication threshold model for coral reefs.

The results from the multimillion dollar Enrichment of Nutrients on Coral Reefs Experiment (ENCORE) on One Tree Island Reef (OTIR) suggest that increased nutrient loads to coral reefs will have little or no effect on the algal growth rates and, hence, on the associated effects that increased algal growth might have on the functioning and stability of coral reefs. However, a comparison of the concentrations of nutrients within the OTIR lagoon with the proposed nutrient threshold concentrations (NTC) for coral reefs suggests that all sites, including the control sites, were saturated with nutrients during ENCORE, and, hence, one would not expect to get any differences between treatments in the algal-growth related measurements. Thus, ENCORE results provide strong support for the proposed NTCs and support the ecological principle that algal productivity and, consequently, the functioning of coral reefs are sensitive to small changes in the background concentrations of nutrients.

Matrix metalloproteinase-8 and -9 are increased at the site of abdominal aortic aneurysm rupture.

Background: Abdominal aortic aneurysm (AAA) expansion is characterized by extracellular matrix degradation and widespread inflammation. In contrast, the processes that characterize AAA rupture are not well understood. The aim of this study was to investigate the proteolytic and cellular activity of ruptured AAA, focusing on matrix metalloproteinases (MMPs) and their inhibitors (TIMPs).

Does carotid endarterectomy lead to a decline in cognitive function or health related quality of life?

Carotid endarterectomy has been shown to reduce the long-term risk of stroke in selected patients. The present study was designed to examine cognitive function and health related quality of life in a series of carotid endarterectomy patients. One hundred and nine patients undergoing carotid endarterectomy were assessed before surgery and at 6 months post op (n = 100) on standard cognitive function tests and quality of life surveys.

Anti-platelet effect of aspirin is substantially reduced after administration of heparin during carotid endarterectomy.

Objectives: Aspirin therapy is usually continued throughout the perioperative period to reduce the risk for thromboembolic stroke and myocardial infarction after carotid endarterectomy (CEA). Aspirin irreversibly binds cyclooxygenase-1, thereby reducing platelet aggregation for the lifetime of each platelet. However, recent research from this unit has shown that aggregation in response to arachidonic acid increases significantly, but transiently, during CEA, which suggests that the anti-platelet effect of aspirin is temporarily reversed.

Clinical outcome of primary infrainguinal subintimal angioplasty in diabetic patients with critical lower limb ischemia.

Purpose: To evaluate the clinical outcome of subintimal angioplasty in diabetic patients with critical limb ischemia (CLI) compared to nondiabetics irrespective of the patency status of the treated arteries.

Methods: The records of 99 consecutive patients (53 men; median age 78.5 years, range 42-92) suffering from CLI who underwent primary infrainguinal subintimal angioplasty in 112 limbs within a 6-month period were studied retrospectively.

Comparison of levels of matrix metalloproteinases, tissue inhibitor of metalloproteinases, interleukins, and tissue necrosis factor in carotid endarterectomy specimens from patients on versus not on statins preoperatively.

We performed an observational study on 137 patients undergoing carotid endarterectomy (CEA). Patients on statins were less likely to have had symptoms in the 4 weeks before CEA (p = 0.0049) and were less likely to have spontaneous cerebral embolization detected by transcranial Doppler (p = 0.

Evaluation of level 1 care facilities for vascular patients.

Background: A surgical acute care unit (SACU) was established within our hospital to specifically provide level 1 care to surgical patients. We assess the impact that this has had on outcome in vascular patients.

Methods: All patients undergoing carotid endarterectomy (CEA) and elective abdominal aortic aneurysm repair (AAA) during the first year of SACU were included in the present study.

Randomized trial of vein versus dacron patching during carotid endarterectomy: long-term results.

Background And Purpose: Overviews of randomized patch trials by the Cochrane Collaboration suggest that a policy of routine patching is preferable to routine primary closure. However, there is no systematic evidence that patch type, whether prosthetic or vein, influences outcome after carotid endarterectomy (CEA).

Methods: Two hundred seventy-three patients were randomized to vein or thin-walled Dacron patch (Hemashield Finesse) closure of the arteriotomy after 276 CEA procedures.

Autotransplantation of unmanipulated bone marrow into scarred myocardium is safe and enhances cardiac function in humans.

Stem cell transplants into damaged myocardium may have the potential to improve cardiac function. We investigated the safety of transplanting unmanipulated autologous bone marrow into infarcted myocardium of patients undergoing coronary bypass surgery and assessed its efficacy to improve cardiac function. Fourteen patients with one or more areas of transmural myocardial infarction were studied.

Beneficial effects of clopidogrel combined with aspirin in reducing cerebral emboli in patients undergoing carotid endarterectomy.

Background: Postoperative thromboembolic stroke affects 2% to 3% of patients undergoing carotid endarterectomy (CEA) and is preceded by 1 to 2 hours of increasing cerebral embolization. Previous work has demonstrated that high rates of postoperative embolization are associated with increased platelet reactivity to adenosine 5'-diphosphate (ADP). Our hypothesis was that preoperative administration of the platelet ADP antagonist clopidogrel could reduce postoperative embolization.

Noninvasive augmentation of microvessel number in patients with peripheral vascular disease.

Objective: Therapeutic angiogenesis has great potential for the treatment of ischemic diseases. One possible route for noninvasive induction of microvessels has recently been suggested by the finding that subcontractile electrical stimulation induces increased vascularization in animals. The present study tests the ability of such stimulation to augment microvessel number in patients with peripheral vascular disease.

Patients' thromboembolic potential after carotid endarterectomy is related to the platelets' sensitivity to adenosine diphosphate.

Unlabelled: Background and purpose Postoperative microemboli in patients undergoing carotid endarterectomy are a significant risk factor for stroke. These emboli can be detected by intraoperative transcranial Doppler monitoring. They are not linked to technical error and are variable between patients.

Percutaneous transluminal angioplasty in the treatment of critical limb ischemia.

Purpose: To assess the role of percutaneous transluminal angioplasty (PTA) to treat critical limb ischemia (CLI) and to relate the changing experience with endovascular treatment of this condition in a major vascular unit.

Methods: A prospective study was performed involving 110 consecutive patients (57 women; mean age 76 years, range 57-99) undergoing balloon angioplasty for critical limb ischemia in 133 limbs. Outcome at 1 year was examined by case note review or questionnaire to determine survival, amputation-free survival, limb salvage, and CLI recurrence.