The TETAMI Trial: The Safety and Efficacy of Subcutaneous Enoxaparin versus Intravenous Unfractionated Heparin and of Tirofiban versus Placebo in the Treatment of Acute Myocardial Infarction for Patients Not Thrombolyzed: Methods and Design

Patients with acute myocardial infarction (AMI) who do not receive early reperfusion therapy are at high risk of reinfarction or death, and the efficacy and safety of antithrombotic therapy in this group of patients has not been evaluated. Enoxaparin is a low-molecular-weight heparin (LMWH) that has previously been shown to reduce the incidence of ischemic events in patients with unstable angina or non–Q-wave MI. The principal aims of the TETAMI study are to investigate the efficacy and safety of treatment with enoxaparin or tirofiban (a glycoprotein IIb/IIIa receptor antagonist) alone or in combination for 2 to 8 days in patients with AMI who are not eligible for early reperfusion therapy. In this 2 by 2 factorial design study approximately 900 patients will be randomly assigned, in a blinded manner, to one of four treatments: enoxaparin alone, enoxaparin plus tirofiban, unfractionated heparin (UFH), or UFH plus tirofiban, with appropriate matched placebos. The primary end point is the composite of death, recurrent AMI, and recurrent angina, analyzed at 30 days after AMI. The design and methods of the TETAMI study are described in this article.     

Cardiac hypertrophy is enhanced in PPAR alpha-/- mice in response to chronic pressure overload

AIMS: Peroxisome proliferator-activated receptor-alpha (PPARalpha) is a nuclear receptor regulating cardiac metabolism that also has anti-inflammatory properties. Since the activation of inflammatory signalling pathways is considered to be important in cardiac hypertrophy and fibrosis, it is anticipated that PPARalpha modulates cardiac remodelling. Accordingly, in this study the hypothesis was tested that the absence of PPARalpha aggravates the cardiac hypertrophic response to pressure overload. METHODS AND RESULTS: Male PPARalpha-/- and wild-type mice were subjected to transverse aortic constriction (TAC) for 28 days. TAC resulted in a more pronounced increase in ventricular weight and left ventricular (LV) wall thickness in PPARalpha-/- than in wild-type mice. Compared with sham-operated mice, TAC did not affect cardiac function in wild-type mice, but significantly depressed LV ejection fraction and LV contractility in PPARalpha-/- mice. Moreover, after TAC mRNA levels of hypertrophic (atrial natriuretic factor, alpha-skeletal actin), fibrotic (collagen 1, matrix metalloproteinase-2), and inflammatory (interleukin-6, tumour necrosis factor-alpha, cyclo-oxygenase-2) marker genes were higher in PPARalpha-/- than in wild-type mice. The mRNA levels of genes involved in fatty acid metabolism (long-chain acyl-CoA synthetase, hydroxyacyl-CoA dehydrogenase) were decreased in PPARalpha-/- mice, but were not further compromised by TAC. CONCLUSION: The present findings show that the absence of PPARalpha results in a more pronounced hypertrophic growth response and cardiac dysfunction that are associated with an enhanced expression of markers of inflammation and extracellular matrix remodelling. These findings indicate that PPARalpha exerts salutary effects during cardiac hypertrophy.     

Mast cell degranulation during abdominal surgery initiates postoperative ileus in mice

BACKGROUND & AIMS: Inflammation of the intestinal muscularis following manipulation during surgery plays a crucial role in the pathogenesis of postoperative ileus. Here, we evaluate the role of mast cell activation in the recruitment of infiltrates in a murine model. METHODS: Twenty-four hours after control laparotomy or intestinal manipulation, gastric emptying was determined. Mast cell degranulation was determined by measurement of mast cell protease-I in peritoneal fluid. Intestinal inflammation was assessed by determination of tissue myeloperoxidase activity and histochemical staining. RESULTS: Intestinal manipulation elicited a significant increase in mast cell protease-I levels in peritoneal fluid and resulted in recruitment of inflammatory infiltrates to the intestinal muscularis. This infiltrate was associated with a delay in gastric emptying 24 hours after surgery. Pretreatment with mast cell stabilizers ketotifen (1 mg/kg, p.o.) or doxantrazole (5 mg/kg, i.p.) prevented both manipulation-induced inflammation and gastroparesis. Reciprocally, in vivo exposure of an ileal loop to the mast cell secretagogue compound 48/80 (0.2 mg/mL for 1 minute) induced muscular inflammation and delayed gastric emptying. The manipulation-induced inflammation was dependent on the presence of mast cells because intestinal manipulation in mast cell-deficient Kit/Kitv mice did not elicit significant leukocyte recruitment. Reconstitution of Kit/Kitv mice with cultured bone marrow-derived mast cells from congenic wild types restored the manipulation-induced inflammation. CONCLUSIONS: Our results show that degranulation of connective tissue mast cells is a key event for the establishment of the intestinal infiltrate that mediates postoperative ileus following abdominal surgery.     

Amelioration of Neurosensory Structure and Function in Animal and Cellular Models of a Congenital Blindness

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Febrile neutropenic events in cancer patients Treatment for fever and neutropenia in young adult patients during intensive chemotherapy for solid tumours

Summary Febrile neutropenic events (FNE) were studied in 90 patients on chemotherapy protocols for solid tumours, from 1986 to 1990. All patients received intensive chemotherapy with a high dose intensity. There were 51 FNE admissions in 31 patients, with an average event rate of 1.6/patient. The average periods of granulocytopenia, fever and admission were 3.5, 2.7 and 5.4 days respectively. The management of FNE consisted of accurate clinical observation and antibiotic treatment if indicated by symptoms of infection or by bacteriological cultures. Only 25 of 51 patients admitted received empiric broad-spectrum antibiotics, while 7 were treated after the results of bacteriological cultures were known. One patient died during granulocytopenia, of interstitial pneumonitis for which no bacteriological source was established. Recurrences of infection after discharge from the hospital were not seen. We conclude that in this group of young adult patients, FNE runs a favourable course. Only a short period of admission and a limited form of antibiotic treatment are needed, minimizing the load on the patient and the costs of their care.Abbreviation FNE febrile neutropenic events     

Forecasting mortality: dynamic assessment of risk in ST-segment elevation acute myocardial infarction.

AIMS: To demonstrate the feasibility and clinical utility of developing dynamic risk assessment models for ST-segment elevation myocardial infarction (STEMI) patients. METHODS AND RESULTS: In 6066 STEMI patients enrolled in the Assessment of the Safety and Efficacy of a New Thrombolytic-3 (ASSENT-3) trial with complete electrocardiographic data, we assessed the probability of 30-day mortality over the following forecasting periods beginning at day 0 (baseline), 3 h, day 2, and day 5 using multiple-logistic regression. These models were validated and simplified in independent samples of 1622 similar fibrinolytic-treated patients from the ASSENT-3 PLUS trial and in 814 STEMI patients undergoing primary percutaneous coronary intervention in the COMplement inhibition in Myocardial infarction treated with Angioplasty (COMMA) trial. The discriminatory power of these predictive models, from baseline to day 5, was excellent (c-statistics 0.80 to 0.87); and their predictive ability was supported by strong gradients in mortality outcomes as the risk score increased. Dynamic modelling also provided information on the change in prognosis over time which may be used to advise more appropriate therapeutic decisions, e.g. the identification of high-risk patients for possible co-interventions. CONCLUSION: Dynamic modelling for STEMI patients enhances the risk assessment and stratification and should provide valuable ongoing guidance for their management.