[Antithrombotics in pre-hospital phase of acute coronary syndromes]

Antithrombotic therapies are the corner stone of acute coronary syndrome management. We have the proof that many of them should be initiated during the prehospital care because their clinical benefit is time-dependent. The hypothesis that anticoagulation therapy is an effective treatment of STEMI, which benefit is time-dependent, is now validated. It is also fair to affirm that GP lIb/IIIa receptor inhibitors are the adjuvant therapy of choice for primary PCI. Indeed, these medications reduce short-term and long-term mortality. This clinical benefit is time dependent. Clopidogrel therapy is probably also a medication of the prehospital phase. It is well established now that the biological efficacy of this pro drug is loading dose dependent. It is also demonstrated that its clinical efficacy depends on the time delay between symptom onset and initiation of the therapy. However, the clinical benefit of prehospital administration remains to be established.

[Prevalence of asymptomatic atherothrombotic lesions and risk of vascular events in patients with documented coronary artery disease]

Coronary arteries are the most frequent location of atherosclerosis. Coronary artery disease is the first cause of death related to atherothrombosis. In addition, patients with a prior history of acute coronary syndromes exhibit a 10% annual risk of recurrence. Although there seems to be a close correlation between the extension of CAD and the severity of atherosclerotic lesions in extra coronary arterial beds, the prevalence of these extracoronary asymptomatic lesions depends on their location. Hence, the prevalence of renal artery disease defined as stenosis > or = 50% or of peripheral artery disease defined as an ABI < 0.9 is estimated to be 20% up to 30%, whereas the prevalence of both carotid artery disease defined as stenosis > or = 70% or aortic aneurysm is estimated to be 5%. Conversely, the annual absolute risk of stroke among CAD patients is estimated at 1% while it remains unknown for vascular events related to PAD or aortic lesions. These data suggest that a systematic screening for asymptomatic extracoronary atherosclerotic lesions among CAD patients cannot be justified without a better knowledge of the prevalence of these lesions. In addition, the identification of the predicting factors for the presence and the development of these asymptomatic lesions is warranted. Finally, the potential benefit in terms of therapeutic intervention of such screening needs to be evaluated. These important issues warrant further clinical studies with appropriate design.

[Screening strategies for the diagnosis of asymptomatic arterial lesions in patients with atherothrombosis]

Atherosclerosis is a ubiquitous inflammatory disease. Patients presenting an acute atherothrombotic event (acute coronary syndrom, stroke, aortic aneurysm, ...) have an increased risk of events in remote arterial territories affected by atherosclerosis. These patients could benefit from systematic screening of asymptomatic atherosclerotic lesions to avoid these complications. For each atherosclerotic territory (coronary artery, carotid artery, aorta, peripheral arteries including renal arteries), we review the methods for screening asymptomatic atherothrombotic lesions which could justify specific treatments: coronary artery stenosis > or = 50%, carotid artery stenosis > or = 60%, renal artery stenosis > or = 50%, and abdominal aortic aneurysm > or = 30 mm. This review shows that non invasive methods (ie, echography, tomodensitometry) are widely available for diagnosis of asymptomatic lesions in carotid and renal arteries, and in the aorta. Despite its invasive caracteristic, coronarory angiography remains the gold-standard for the diagnosis of coronary artery disease. However, cardiac multi-slices CT-scan appears a promising technique for asymptomatic patients.

[Does diabetes affect the choice of pharmaceutical treatment in coronary artery disease?]

Coronary artery disease is the principal cause of death in diabetic patients. The choice of pharmaceutical treatment used in diabetic patients with coronary artery disease should be based on that of non-diabetic coronary patients (BASIC). However, diabetes has its own specificities. First of all, dietetic measures and physical exercise should be continually encouraged. The questions about the basic treatment concern mainly the choice of oral platelet antiaggregants and the need to associate these drugs systematically and definitively. With regards to the management of acute coronary syndromes, the important point is the improved short and long-term benefits of GP IIb/IIIa on the survival of diabetic coronary patients, especially when angioplasty is performed. Finally, intravenous insulin therapy is promising in the initial phase of treatment of acute coronary syndromes with better defined blood glucose objectives.

New Devices Designed to Improve the Long-Term Results of Endovascular Treatment of Intracranial Aneurysms. A Proposition for a Randomized Clinical Trial to Assess their Safety and Efficacy

SUMMARY

Endovascular coiling can improve the outcome of patients with ruptured intracranial aneurysms, but angiographic recurrences are frequent compared to surgical clipping. New coils or devices have been introduced to improve long-term results of endovascular treatment but none have been the object of a valid clinical trial. We have proposed a multicentric randomized double-blind study comparing radioactive and standard coil occlusion of aneurysms. The purpose of this article is to review issues that are specific to the design of clinical trials to assess embolic agents that could improve the long-term efficacy of endovascular treatment of intracranial aneurysms. The proposed trial is a randomized, multi-center, prospective, controlled trial comparing the new generation coils to standard platinum coils. Blinding, if at all possible, is preferable to minimize bias, at least for follow-up angiographic studies that should cover a period of 18 months. All patients with an intracranial aneurysm eligible for endovascular treatment would be proposed to participate. The study would enrol approximately 500 patients equally divided between the two groups, recruited within two years, to demonstrate a decrease in the recurrence rate, the primary outcome measure, from 20% to 10%. Secondary outcome measures should assure that complications, initial clinical and angiographic results remain unchanged. Independent data safety and monitoring committees are crucial to the credibility of trials and to ensure scientific rigor and objectivity. The scientific demonstration of an improved long-term efficacy, without significant compromise regarding safety, is mandatory before considering the widespread use of a new embolic device for the endovascular treatment of aneurysms.

A randomized trial on the safety and efficacy of endovascular treatment of unruptured intracranial aneurysms is feasible

SUMMARY

The safety and efficacy of endovascular treatment of unruptured intracranial aneurysms remain undetermined. A randomized trial may be the best way to demonstrate the potential benefits of endovascular management. We propose a randomized, prospective, controlled trial comparing the incidence of subarachnoid haemorrage of patients treated by endovascular coiling as compared to conservative management. We would also study a composite outcome combining SAH and the morbidity of treatment. All patients with one or more unruptured aneurysm >> 3 mm eligible for endovascular treatment would be proposed to participate. The study would be conducted in 40-50 centres. The entire study would enrol 1800 patients, recruited over three years and followed for five years, but would be preceded by a feasibility study on 200 patients. A randomized trial comparing endovascular and conservative treatment could have an important impact on the clinical management of intracranial aneurysms.

Impact of prior use or recent withdrawal of oral antiplatelet agents on acute coronary syndromes

BACKGROUND

Oral antiplatelet agents (OAAs) can prevent further vascular events in cardiovascular disease. How prior use or recent discontinuation of OAA affects clinical presentation of acute coronary syndromes (ACS) and clinical outcomes (death, myocardial infarction [MI]) is unclear.

METHODS AND RESULTS

We studied and followed up for up to 30 days a cohort of 1358 consecutive patients admitted for a suspected ACS; of these, 930 were nonusers, 355 were prior users of OAA, and 73 had recently withdrawn OAA. Nonusers were at lower risk, more frequently presented with ST-elevation MI on admission, and more frequently had Q-wave MI at discharge than prior users (36.6% versus 17.5%, P<0.001; and 47.8% versus 28.2%, P<0.001, respectively). However, there was no difference regarding the incidence of death or MI at 30 days between nonusers and prior users (10.3% versus 12.4%, P=NS). In addition, prior users experienced more major bleeds within 30 days compared with nonusers (3.4% versus 1.4%, respectively; P=0.04). Recent withdrawers were admitted on average 11.9+/-0.8 days after OAA withdrawal. Interruption was primarily a physician decision for scheduled surgery (n=47 of 73). Despite a similar cardiovascular risk profile, recent withdrawers had higher 30-day rates of death or MI (21.9% versus 12.4%, P=0.04) and bleedings (13.7% versus 5.9%, P=0.03) than prior users. After multivariate analysis, OAA withdrawal was found to be an independent predictor of both mortality and bleedings at 30 days.

CONCLUSIONS

Among ACS patients, prior users represent a higher-risk population and present more frequently with non-ST-elevation ACS than nonusers. Although patients with a recent interruption of OAA resemble those chronically treated by OAA, they display worse clinical outcomes.

Anti-Xa Activity Relates to Survival and Efficacy in Unselected Acute Coronary Syndrome Patients Treated With Enoxaparin

Background— Low-molecular-weight heparin (LMWH) is recommended in the treatment of unstable angina (UA)/non–ST-segment–elevation myocardial infarction (NSTEMI), but no relationship has ever been shown between anticoagulation levels obtained with LMWH treatment and clinical outcomes.

Methods and Results— In all, 803 consecutive patients with UA/NSTEMI were treated with subcutaneous enoxaparin and were followed up for 30 days. The recommended dose of enoxaparin of 1 mg/kg BID was used throughout the population except when physicians decided on dose reduction because of a history of a recent bleeding event or because of a high bleeding risk. Anti–factor Xa activity was >0.5 IU/mL in 93% of patients; subtherapeutic anti-Xa levels (<0.5 IU/mL) were associated with lower doses of enoxaparin. The 30-day mortality rate was significantly associated with low anti-Xa levels (<0.5 IU/mL), with a >3-fold increase in mortality compared with the patients with anti-Xa levels in the target range of 0.5 to 1.2 IU/mL ( P =0.004). Multivariate analysis revealed low anti-Xa activity as an independent predictor of 30-day mortality at least as strong as age, left ventricular function, and renal function. In contrast, anti-Xa activity did not predict major bleeding complications within the range of anti-Xa levels observed in this study.

Conclusions— In this large unselected cohort of patients with UA/NSTEMI patients, low anti-Xa activity on enoxaparin treatment is independently associated with 30-day mortality, which highlights the need for achieving at least the minimum prescribed anti-Xa level of 0.5 IU/mL with enoxaparin whenever possible.

Subcutaneous enoxaparin with early invasive strategy in patients with acute coronary syndromes

BACKGROUND

Subcutaneous enoxaparin during at least 48 hours provides adequate anticoagulation and good clinical results in patients with non-ST-segment elevation acute coronary syndromes undergoing percutaneous coronary intervention (PCI).

METHODS

In this nonrandomized retrospective study, we compared 347 patients with non-ST-segment elevation acute coronary syndromes who underwent rapid PCI after only 2 injections of subcutaneous enoxaparin (EI, n = 117) to those referred later to the catheterization laboratory with >or=3 injections (DI, n = 230). We measured anti-Xa at the time of PCI and evaluated bleeding and major ischemic events (death/myocardial infarction) at 30 days.

RESULTS

Patients in the EI group more frequently received glycoprotein IIb/IIIa inhibitors and clopidogrel preceding PCI than did patients in the DI group (58.1% vs 31.7%, P <.0001 for glycoprotein IIb/IIIa inhibitors and 68.4% vs 40.4% for clopidogrel pretreatment, P <.0001, respectively). The anti-Xa activity measured at the time of catheterization (0.92 +/- 0.04 U/mL vs 0.96 +/- 0.02 U/mL, EI vs DI, P =.25) and the injection-to-catheterization times (5.6 +/- 0.2 h vs 5.2 +/- 0.1 h, EI vs DI, P =.17) were similar in both groups. The 30-day bleeding rates of 1.7% and 4.8% in the EI and DI strategies were found to be equivalent with a significant non-inferiority test for the EI strategy (P <.05). There was a nonsignificant trend for less death or myocardial infarction at 30 days in the EI group compared to the DI group (4.3% vs 7.0%, non-inferiority test not significant).

CONCLUSION

A rapid invasive strategy with only 2 subcutaneous injections of enoxaparin provides similar levels of anticoagulation, and is associated with a favorable trend for ischemic events and with safety equivalent to a more prolonged "upstream" treatment with enoxaparin.

[Thrombosis caused by active rapamycin stents]

We report the case history of a patient aged 68 years presenting with a recurrence of anterior myocardial infarction complicated by cardiogenic shock with a thrombosis of an active rapamycin stent 77 days following the angioplasty procedure. This was provoked by stopping platelet anti-aggregant treatment, a diabetic background and in the context of scheduled surgery for cancer recurrence. Recent data in the literature combined with our observations prompt the continuation of anti-aggregant bi therapy for at least 9 months after endoprosthesis insertion even if an active stent is used. In the case where surgery is envisaged, it is necessary to wait at least 6 months after the rapamycin stent revascularisation procedure. If an extra-cardiac procedure is envisaged during the angioplasty, it would be preferable to not use an active stent.

Influence of γ′ Fibrinogen Splice Variant on Fibrin Physical Properties and Fibrinolysis Rate

Objective— A splice variant of fibrinogen, γ′, has an altered C-terminal sequence in its gamma chain. This γA/γ′ fibrin is more resistant to lysis than γA/γA fibrin. Whether the physical properties of γ′ and γA fibrin may account for the difference in their fibrinolysis rate remains to be established.

Methods and Results— Mechanical and morphological properties of cross-linked purified fibrin, including permeability (Ks, in cm 2 ) and clot stiffness (G′, in dyne/cm 2 ), were measured after clotting γA and γ′ fibrinogens (1 mg/mL). γ′/γ′ fibrin displayed a non-significant decrease in the density of fibrin fibers and slightly thicker fibers than γA/γA fibrin (12±2 fiber/10 −3 nm 3 versus 16±2 fiber/10 −3 nm 3 and 274±38 nm versus 257±41 nm for γ′/γ′ and γA/γA fibrin, respectively; P =NS). This resulted in a 20% increase of the permeability constant (6.9±1.7 10 −9 cm 2 versus 5.5±1.9 10 −9 cm 2 , respectively; P =NS). Unexpectedly, γ′ fibrin was found to be 3-times stiffer than γA fibrin (72.6±2.6 dyne/cm 2 versus 25.1±2.3 dyne/cm 2 ; P <0.001). Finally, there was a 10-fold decrease of the fibrin fiber lysis rate.

Conclusions— Fibrinolysis resistance that arises from the presence of γA/γ′ fibrinogen in the clot is related primarily to an increase of fibrin cross-linking with only slight modifications of the clot architecture.

[Role of glycoprotein IIb/IIIa inhibitors in the management of acute coronary syndromes]

Antiplatelet therapy is a cornerstone in the medical management of acute coronary syndromes. Three classes of antiplatelet drugs are available in this setting: acetylsalicylic acid, thienopyridines, and glycoprotein IIb/IIIa antagonists. During the last ten years, numerous clinical trials have been conducted in large populations of patients suffering from acute coronary syndromes. Further investigations are in progress. In the light of these results, the respective roles of the different antiplatelet drugs have been more precisely defined, in terms of class preference as well as in terms of the combination of several antiplatelet drugs and of antiplatelet drugs with other therapies, including non fractionated--or low molecular weight--heparin and non-invasive or invasive revascularisation procedures. In the present article, we review the results of the major published or non published trials that addressed the role of glycoprotein IIb/IIIa antagonists in the management of acute coronary syndromes. Based on these results, the current therapeutic guidelines for clinical practice issued by the American and European cardiology societies are given in the conclusion, with their level of evidence.

Tattooing and transfusion-transmitted diseases in Brazil: a hospital-based cross-sectional matched study

BACKGROUND

Presence of tattoos has been a criterion for temporary deferral of blood donors. Scientific evidence remains equivocal regarding the association between tattooing and transfusion-transmitted diseases (TTDs).

METHODS

A cross-sectional matched study was undertaken among adults attending a Brazilian hospital and blood bank. The exposure of interest was having at least one permanent tattoo, and the outcomes were the presence of serological markers for the following TTDs: hepatitis B virus (HBV), hepatitis C virus (HCV) and human immunodeficiency virus (HIV) infections, syphilis, and Chagas' disease. Exposed and unexposed subjects were matched on age, sex, and main clinical complaint. Associations were assessed by odds ratios (ORs), adjusted for confounders by unconditional logistic regression.

FINDINGS

The study recruited 345 subjects, 182 with tattoos. Having a tattoo was associated with HCV (OR: 6.41; 95% confidence interval (CI) 1.29, 31.84), and with having at least one positive test for any TTD (OR: 2.05, 95% CI: 1.11, 3.81). No statistically significant associations were found between tattooing and HBV or HIV infection, syphilis or Chagas' disease, but these results are inconclusive given the large CI obtained.

INTERPRETATION

Having a tattoo is not an important indicator for testing positive for a TTD, except for HCV infection. Taking into consideration the increasing prevalence of tattooing in the general population, the absolute need of a safe and sustainable blood supply and optimization of the cost-effectiveness of screening blood donors, further research on tattoos is urgently required.

Acute release of plasminogen activator inhibitor-1 in ST-segment elevation myocardial infarction predicts mortality

BACKGROUND

A few studies have suggested that von Willebrand factor (vWF) or plasminogen activator inhibitor-1 (PAI-1) can be associated with outcomes of acute coronary syndromes. The present study was designed to assess the acute release of these markers in ST-segment elevation myocardial infarction (STEMI) and their relations to death.

METHODS AND RESULTS

In 153 consecutive patients with STEMI, vWF and PAI-1 antigens were measured on admission (H0) and 24 hours later (H24). At 30 days, the death rate was 7.2%. Heart failure (Killip stage > or =3) on admission was present in 13.7% of patients. The acute release of PAI-1 (H24-H0, in ng/mL) and of vWF (H24-H0, in %) was dramatically higher in patients who died than in those who survived (46.9+/-26.3 versus -0.6+/-2.8 ng/mL, P=0.0001 and 65.8+/-20.0% versus 10.0+/-5.1%, P=0.004 for PAI-1 and vWF, respectively) and in patients developing heart failure compared with those without (24.8+/-10.1 versus -1.1+/-3.3 ng/mL, P=0.004 and 47.3+/-11.0% versus 8.1+/-5.6%, P=0.005 for PAI-1 and vWF, respectively). The release of PAI-1 correlated weakly with the left ventricular ejection fraction (R=-0.195, P=0.01) and the peak of troponin (R=0.149, P=0.045). Postangioplasty TIMI-3 flow and the acute release of PAI-1 were the only 2 independent predictors of death at 30 days.

CONCLUSIONS

The acute release of vWF and PAI-1 over the first 24 hours of STEMI is associated with death and heart failure. The acute rise of PAI-1 is also a strong independent predictor of death at 30 days.

Compact disc with both numeric and genomic information as DNA microarray platform

The compact disc (CD) is an ideal toolfor reading, writing, and storing numeric information. It was used in this work as a support for constructing DNA microarrays suited for genomic analysis. The CD was divided into two functional areas: the external ring of the CD was used for multiparametric DNA analysis on arrays, and the inner portion was usedfor storing numeric information. Because polycarbonate and CD resins autofluoresce, a colorimetric method for DNA microarray detection was used that is well adaptedfor the fast detection necessary when using a CD reader. A double-sided CD reader was developed for the simultaneous analysis of both array and numeric data. The numeric data are engraved as pits in the CD tracks and result in the succession of 0/1, which results from the modulation of the laser reflection when one reads the edges of the pits. Another diffraction-based laser was placed above the CD for the detection of the DNA targets on the microarrays. Both readersfit easily in a PC tower. Both numeric and genomic information data were simultaneously acquired, and each array was reconstituted, analyzed, and processed for quantification by the appropriate software.

Lessons learned: Outcomes and methodology of a coping skills intervention trial comparing individual and group formats for patients with cancer

OBJECTIVE

Nucare, a short-term psychoeducational coping skills training intervention was evaluated in a randomized controlled clinical trial (RCT) of 225 newly diagnosed breast and colon cancer patients.

METHOD

Measures of psychosocial distress, well being and optimism were evaluated every four months during a one-year period. Patients were randomized to one of four arms: Nucare presented in an individual basis; Nucare presented in a group format; a non-directive supportive group; and a no-intervention control. The interventions were provided in five sessions of ninety minutes each.

RESULTS

Patients with breast cancer who received Nucare presented in an individual format showed more significant improvements in well-being over time compared to those in the control and group arms.

CONCLUSIONS

We were unable to develop functioning groups within the RCT. Partial explanations for the latter finding include the structural limitations of the RCT: the groups were small, difficult to schedule and patients indicated that they would have preferred to choose whether or not to participate in a group. The positive changes in women with breast cancer who received Nucare persisted at 12 months.

Tattooing and risk for transfusion-transmitted diseases: the role of the type, number and design of the tattoos, and the conditions in which they were performed

Tattoos have been shown to be associated with transfusion-transmitted diseases (TTDs), particularly hepatitis B virus (HBV) and hepatitis C virus (HCV) infections. Very little is known about the association between different categories of tattoos and TTDs. In a cross-sectional study in Brazil, we studied 182 individuals with tattoos and assessed the odds of testing positive for a TTD according to tattoo type, number, design and performance conditions. Major findings were significant associations between an increasing number of tattoos and HBV infection (odds ratio (OR) of 2.04 for two tattoos and 3.48 for > or = 3 tattoos), having a non-professional tattoo and testing positive for at least one TTD (OR = 3.25), and having > or = 3 tattoos and testing positive for at least one TTD (OR = 2.98). We suggest that non-professional tattoos and number of tattoos should be assessed as potential deferral criteria in screening blood donors.

Selection of subjects for hospital-based epidemiologic studies based on outward manifestations of disease

Selection of controls with the same outward manifestations of disease as the case group has been proposed as a means of avoiding selection bias in hospital-based case-control studies. The same strategy, however, can lead to selection bias in registry-based case-control studies that use control diseases with similar manifestations whose diagnoses might have been associated with the exposure. Matching exposed and unexposed subjects by outward manifestation of disease can be used in cohort and cross-sectional studies aiming at decreasing selection bias. This strategy in these study designs may lead to overmatching, but this will not bias the relative-risk estimates. Efficiency considerations in applying this strategy require further investigation.

[Review and future perspectives on low-molecular-weight heparin]

Low molecular weight heparins appear to be a better choice in patients with unstable angina than unfractionated heparin. Their favourable pharmacokinetic profile allows an excellent predictable dose-response with a subsequent rapidly effective and stable anticoagulation, which is ideal in the setting of percutaneous coronary intervention. Although direct comparisons between LMWH and UH are limited, substantial evidence exists that patients receiving LMWH can be safely brought to cardiac catheterization. Therefore, previous concern regarding transitioning such therapy from the medical service to the cardiac catheterization laboratory should not impede the upstream use of these agents. Direct i.v. injection of LMWH in the setting of elective PCI have also been shown to be safe and effective. Although UH remains an option in conjunction with GP IIb/IIIa inhibitors, there is substantial evidence that LMWH and GP IIb/IIIa inhibitor therapy can be used safely in combination. Patients with either chronic renal failure, mechanical valves or atrial fibrillation are other important issues which deserve additional prospective evaluation of the safety and the efficacy of LMWH. Development of a biological assay for monitoring either LMWH or GP IIb/IIIa receptor antagonists is another important issue in the setting of antithrombotic combinations which are now commonplace.

[Antithrombotic therapy in the acute phase of unstable angina]

Low molecular weight heparins appear to be a better choice in patients with unstable angina than unfractionated heparin. In addition, the excellent predictable dose-response makes them suitable to prevent ischemic complications of percutaneous coronary intervention. Although direct comparisons between LMWH and UH are limited, substantial evidence exists that patients receiving LMWH can be safely brought to cardiac catheterization. Therefore, previous concern regarding transitioning such therapy from the medical service to the cardiac catheterization laboratory should not impede the upstream use of thèse agents. Although UH remains an option in conjunction with GP IIB/IIIa inhibitors, there is substantial evidence that LMWH and GP IIb/IIIa inhibitor therapy can be used safely in combination. Although GP IIb/IIIa inhibitors are very potent to prevent ischemic events after percutaneous coronary interventions, their benefit in the medical management of unstable angina is much more modest. ADP receptor antagonists reduce major ischemic events in combination with aspirin in the medical management of unstable angina patients but also when PCI is planned. Their combination with GP IIB/IIIa receptor antagonist does not impair the benefit of GP IIb/IIIa antagonists. The development of biologic tools to monitor these antithrombotic regimen is highly warranted especially in high risk patients (chronic renal failure, elderly).

Promotion of breastfeeding intervention trial (PROBIT): a cluster-randomized trial in the Republic of Belarus. Design, follow-up, and data validation

This paper summarizes the objectives, design, follow-up, and data validation of a cluster-randomized trial of a breastfeeding promotion intervention modeled on the WHO/UNICEF Baby-Friendly Hospital Initiative (BFHI). Thirty-four hospitals and their affiliated polyclinics in the Republic of Belarus were randomized to receive BFHI training of medical, midwifery, and nursing staffs (experimental group) or to continue their routine practices (control group). All breastfeeding mother-infant dyads were considered eligible for inclusion in the study if the infant was singleton, born at > or = 37 weeks gestation, weighed > or = 2500 grams at birth, and had a 5-minute Apgar score > or = 5, and neither mother nor infant had a medical condition for which breastfeeding was contraindicated. One experimental and one control site refused to accept their randomized allocation and dropped out of the trial. A total of 17,795 mothers were recruited at the 32 remaining sites, and their infants were followed up at 1, 2, 3, 6, 9, and 12 months of age. To our knowledge, this is the largest randomized trial ever undertaken in area of human milk and lactation. Monitoring visits of all experimental and control maternity hospitals and polyclinics were undertaken prior to recruitment and twice more during recruitment and follow-up to ensure compliance with the randomized allocation. Major study outcomes include the occurrence of > or = 1 episode of gastrointestinal infection, > or = 2 respiratory infections, and the duration of breastfeeding, and are analyzed according to randomized allocation ("intention to treat"). One of the 32 remaining study sites was dropped from the trial because of apparently falsified follow-up data, as suggested by an unrealistically low incidence of infection and unrealistically long duration of breastfeeding, and as confirmed by subsequent data audit of polyclinic charts and interviews with mothers of 64 randomly-selected study infants at the site. Smaller random audits at each of the remaining sites showed extremely high concordance between the PROBIT data forms and both the polyclinic charts and maternal interviews, with no evident difference in under- or over-reporting in experimental vs control sites. Of the 17,046 infants recruited from the 31 participating study sites, 16,491 (96.7%) completed the study and only 555 (3.3%) were lost to follow-up. PROBIT's results should help inform decision-making for clinicians, hospitals, industry, and governments concerning the support, protection, and promotion of breastfeeding.

Colorimetric silver detection of DNA microarrays

Development of microarrays has revolutionized gene expression analysis and molecular diagnosis through miniaturization and the multiparametric features. Critical factors affecting detection efficiency of targets hybridization on microarray are the design of capture probes, the way they are attached to the support, and the sensitivity of the detection method. Microarrays are currently detected in fluorescence using a sophisticated confocal laser-based scanner. In this work, we present a new colorimetric detection method which is intented to make the use of microarray a powerful procedure and a low-cost tool in research and clinical settings. The signal generated with this method results from the precipitation of silver onto nanogold particles bound to streptavidin, the latter being used for detecting biotinylated DNA. This colorimetric method has been compared to the Cy-3 fluorescence method. The detection limit of both methods was equivalent and corresponds to 1 amol of biotinylated DNA attached on an array. Scanning and data analysis of the array were obtained with a colorimetric-based workstation.

Enoxaparin in unstable angina patients with renal failure

The dosage of the subcutaneous low molecular weight heparin enoxaparin in unstable angina patients undergoing coronary angiogram and coronary angioplasty depends clearly on the renal function. It should be significantly reduced to 64% of the standard dose (1 mg/kg per 12 h) in patients with severe renal failure (creatinine clearance<30 ml/min) to provide a safe anticoagulant profile.

Effects of Abciximab on the Architecture of Platelet-Rich Clots in Patients With Acute Myocardial Infarction Undergoing Primary Coronary Intervention

Background —Abciximab plus aspirin improves the TIMI 3 flow rate of the infarct-related artery in patients treated with either percutaneous coronary intervention or thrombolysis. The present study investigated whether the reperfusion efficacy of abciximab relates to modifications of clot architecture in patients admitted for acute myocardial infarction (AMI).

Methods and Results —A total of 23 AMI patients in the Abciximab before Direct angioplasty and stenting in Myocardial Infarction Regarding Acute and Long term follow-up (ADMIRAL) trial received, in a double-blind fashion, either abciximab (n=13) or placebo (n=10) before primary stenting. Viscoelastic (G′ in dyne/cm 2 ) and morphological (mean platelet aggregate surface area [SAG] in μm 2 ) indexes of ex vivo platelet-rich clots (PRC) were assessed in a double-blind fashion before and after the bolus administration of abciximab or placebo. G′ and SAG reflect the mechanical and morphological impact of activated platelets on the PRC fibrin network, respectively. Abciximab administration reduced G′ by 63% ( P =0.0001) and SAG by 65% ( P =0.0007), and no effect was seen in the placebo group. These abciximab-related changes increased fibrin exposure as a consequence of the platelet-aggregate surface reduction and may have improved endogenous fibrinolysis. These effects were identified in all patients, independent of previous heparin administration.

Conclusions —Abciximab dramatically reduces platelet aggregate size and increases the fibrin accessibility of ex vivo PRC in AMI patients. These modifications could participate in the better coronary artery patency observed with abciximab.