[Prolongation of anti vitamin K treatment for 18 months versus placebo after 6 months treatment of a first episode of ideopathic pulmonary embolism: a mutlicentre, randomised double blind trail. The PADIS-EP Trial]

BACKGROUND

After stopping a 3 to 6 months course of oral anticoagulation for a first episode of idiopathic venous thromboembolism (VTE), the risk of recurrent VTE is high (10% per year). In this setting, international guidelines recommend at least 6 months treatment. However, this recommendation is not satisfactory for the following reasons: (1) no randomized trial has compared 6 months to extended duration (2 years) anticoagulation; and (2), even though the frequency of recurrent VTE is similar after pulmonary embolism (PE) and deep vein thrombosis (DVT), the fatality rate of recurrent VTE after PE is higher than that after DVT.

METHODS

A French multicentre double blind randomized trial. The main objective is to demonstrate, after a first episode of symptomatic idiopathic PE treated for 6 months using a vitamin K antagonist, that extended anticoagulation for 18 months (INR between 2 and 3) is associated with an increased benefit / risk ratio (recurrent VTE and severe anticoagulant-related bleeding) compared to placebo. The double blind evaluation is ensured using by active warfarin and placebo, and blinded INR. The protocol was approved by the ethics board of the Brest Hospital on the 7th of March 2006. For an alpha risk of 5% and a beta risk of 20%, the estimated sample size is 374 patients.

EXPECTED RESULTS

This study has the potential to: (1) demonstrate that the benefit / risk ratio of extended anticoagulation for 18 months is higher than that observed with placebo in patients with a first episode of idiopathic PE initially treated for 6 months, during and after the treatment period; and (2) to validate or invalidate the contribution of isotope lung scans, lower limb Doppler ultrasound and D-Dimer at 6 months of treatment as predictors of recurrent VTE (medico-economic analysis included).

Controlled release of drugs from multi-component biomaterials

In order to control their release, drugs are encapsulated into systems which are expected to provide a certain site with a predetermined amount of drug over a well-defined period of time. Here we report on a multi-component drug delivery biomaterial that consists of a hydrogel matrix in which drug-loaded biodegradable microcarriers are dispersed, and whose potential applications could be found in the design of implantable devices with long-term activity, as required by contraceptive and hormone replacement treatments. The release profile of the drug can actually be tuned by the complex interplay of several release mechanisms, including the permeability and eventually the degradation rate of the microcarriers and the diffusion through the hydrogel. The hydrogel consisted of 2-hydroxyethyl methacrylate cross-linked by ethylene glycol dimethacrylate. The microcarriers were biodegradable poly-epsilon-caprolactone (PCL) microspheres in which active molecules, such as levonorgestrel (LNG), were encapsulated. The hydrogels were characterized by water swelling, thermal properties, LNG diffusion through drug-free and drug-depleted hydrogel membranes and LNG release from devices with drug dispersed in the hydrogel. The PCL microspheres were observed by scanning electron microscopy; their size distribution, LNG loading and release were also investigated. The hydrogel-microsphere assemblies were characterized in terms of the distribution of the microspheres within the hydrogel, water swelling and the release of the encapsulated molecules. The developed device, due to its composite structure, has the ability to combine several release mechanisms, leading to drug release obeying zero-order kinetics for most of the time.

[A secondary bleeding false aneurysm of the superomedial genicular artery after distal femoral epiphysiodesis: a case report]

A 16-year-old male developed a false aneurysm of the superomedial genicular artery five weeks after medial distal femoral epiphysiodesis. The aneurysm was revealed by inexhaustible bleeding from the medial aspect of the knee and the presence of acute hemorrhage which resolved spontaneously. Physical examination disclosed disunion of the surgical wound at the apex of a pulsatory tumefaction over the medial aspect of the knee. AngioCT enabled the diagnosis of a false aneurysm of the superomedial genicular artery. Emergency surgery was undertaken to drain the hematoma and exclude the false aneurysm by ligating the superomedial genicular artery.

Résection de la rangée proximale des os du carpe

PURPOSE OF THE STUDY

Resection of the proximal row of the carpus which simplifies the radiocarpal joint is mainly performed for advanced collapse. With the development of several therapeutic alternatives, further study of outcome is warranted to better identify indications.

MATERIAL AND METHODS

Twenty-five patients who underwent proximal row carpectomy between January 1999 and February 2004 were reviewed clinically and radiologically at 30 months mean follow-up. Three main etiologies were noted: scaphoid fracture (n=9), scapholunate dissociation (n=9), Kienböck disease (n=6). A posterior approach was used for all patients. Outcome was assessed clinically (pain, force, mobility), radiologically (carpal height, radiocapital space), and subjectively by the patient. Resumption of occupational activity was noted as were the Cooney and Culp scores.

RESULTS

Average flexion-extension was 60 degrees . Average wrist force was 65% of the healthy side. Pain improved in 88% of wrists and the mean subjective score was 15.2. The mean Cooney and Culp scores were 58 and 67.8 respectively. A reduction in the height of the new articular space was not correlated with less favorable clinical outcome. Outcome in patients with Kienböck disease were less favorable than in trauma patients but the difference did not reach significance.

DISCUSSION

First row carpectomy is a paliative procedure which should only be performed when conservative treatment is no longer a valid option. Indications should be limited to Watson grade II, before cartilaginous damage affects the head of the capitatum. New techniques such as fusion-shortening, theoretically similar to resection, can now be used for advances collapse. We prefer resection over four-bone arthrodesis because of the lower risk of complications. In Kienböck disease, first row carpectomy should only be used for selected patients (Lichtmann III) due to the risk of early degeneration of the capitatum and radius heads.

[The transfer of an automated method for the determination of noradrenaline in human urine: using total error as decision criterion]

Two new statistical approaches based on the total error of measurements were applied to the transfer of an automated method for the determination of noradrenalin in human urine by LC-ECD coupled on-line to SPE. They showed that the receiving laboratory was mastering the analytical procedure allowing it to use the method in routine. Furthermore the risk based approach gave guarantee that the risk to have future measurements out of specification in the receiving laboratory was smaller than 5%, therefore being a risk management tool.

[Staphylococcus aureus: role and impact in the treatment of nosocomial pneumonia]

INTRODUCTION

Staphylococcus aureus (SA) has acquired a leading role in nosocomial pneumonia in terms of both frequency and severity, and poses therapeutic problems, namely antibiotic resistance and difficulties in the management of anti-staphylococcal drugs.

STATE OF THE ART

Epidemiological data confirm that SA is implicated in almost a quarter nosocomial pneumonias, of which about a half are due to methicillin resistant SA (MRSA) in France. The pathophysiology of these infections most often involves inhalation following oropharyngeal carriage. In addition to the risk factors common to all nosocomial pneumonias there are the particular roles of head injury and coma, leading to an increased frequency of SA infection in neuro-surgical patients.

PERSPECTIVES

The non-specific clinical picture, the grave prognosis of these pneumonias and the ineffectiveness against MRSA of the antibiotics used in the treatment of Gram negative infections make empirical treatment difficult.

CONCLUSION

In addition to the antibiotics classically active against SA (notably methicillin for sensitive strains and glycopeptides for MRSA) new agents may allow improvement in the treatment of these patients, even if their place is not yet definitively established.

La tuberculose péritonéale : une entité toujours présente. À propos de quatre observations

INTRODUCTION

Tuberculous peritonitis, a major problem in developing country, occurs preferentially in immigrant population and in patients with acquired immune deficiency syndrome (AIDS). Although rare in France, it did not disappear and epidemiological, clinical and therapeutic approach deserve to be reminded.

EXEGESIS

We reported 4 patients (immigrants in two cases), occurred in caucasian and African persons (one with AIDS). Disease was characterized by fever, abdominal pain, anorexia, weight loss and ascites. Biological and radiological were unconclusive. Cell count analysis from ascitic fluid show a lymphocytic predominance with negative direct smear for Ziehl-Neelsen strain. Tuberculous peritonitis was established with combined visual and histological diagnosic laparoscopic examination.

CONCLUSION

These observations have the interest to underline that tuberculous peritonitis must be evoked in case of lymphocytic ascitis. We believe an aggressive diagnostic approach, particulary with peritoneal biopsy, is warranted for the diagnosis of tuberculous peritonitis. Validity of PCR amplification is ascitic fluid still needs to be established.

Polymer blends used for the aqueous coating of solid dosage forms: importance of the type of plasticizer

The aim of this study was to investigate the importance of the type of plasticizer in polymer blends used for the coating of solid dosage forms, comparing a lipophilic and a hydrophilic plasticizer (dibutyl sebacate (DBS) and triethyl citrate (TEC)). In vitro drug release from propranolol hydrochloride (propranolol HCl)-loaded pellets coated with blends of ethyl cellulose (EC) and Eudragit L (100:0, 75:25, 50:50, 25:75 and 0:100 w/w) was investigated at low as well as at high pH. To better understand the underlying mass transport mechanisms, the physicochemical properties of the film coatings (e.g. mechanical resistance, water uptake and dry weight loss behavior) were determined. Interestingly, drug release strongly depended on the type of plasticizer. Importantly, not only the slope but also the shape of the release curves was affected, indicating that the chemical nature of the plasticizer plays a major role for the underlying drug release mechanisms. Diffusion through the intact polymer coatings and/or through water-filled cracks was found to be dominating for the control of drug release. The relative importance of these pathways strongly depended on the polymer blend ratio and type of plasticizer. In contrast to DBS, TEC rapidly leached out of the coatings, resulting in decreasing mechanical resistances of the films and, thus, facilitated crack formation. In addition, the hydrophilicity of the plasticizer significantly affected the water uptake behavior of the film coatings and, hence, changes in the coatings' toughness and drug permeability. Also the relative affinity of the plasticizer to the different polymers was found to be of significance. In contrast to TEC, DBS has a higher affinity to EC than to Eudragit L, resulting in potential redistributions of this plasticizer within the polymeric systems and changes in the release profiles during storage. Importantly, these effects could be avoided with appropriate curing conditions and preparation techniques for the coating dispersions.

Living with uncertainty: genetic imprints of climate shifts in East Pacific anchovy (Engraulis mordax) and sardine (Sardinops sagax)

In the upwelling zone of the northeastern Pacific, cold nutrient-rich conditions alternate with warm nutrient-poor intervals on timescales ranging from months to millennia. In this setting, the abundances of Pacific sardine (Sardinops sagax) and northern anchovy (Engraulis mordax) fluctuate by several orders of magnitude, with sardine dominating during warm conditions and anchovy dominating during cool conditions. Two population models can explain the response of these fishes to adverse conditions. Under the basin model, species distributions contract to a central (optimal) range during population crashes. Expectations of this model may include a single range-wide population with a decline in genetic diversity on both sides of a central refuge. In contrast, the self-recruitment model invokes a series of local oceanographic domains that maintain semi-isolated subpopulations. During adverse conditions, some subpopulations cannot complete the life cycle within the local environment and are extirpated. Expectations of this model include some degree of population genetic structure and no clear gradient in genetic diversity. We examined mitochondrial DNA cytochrome b sequences to assess these competing models for anchovy (N = 196; 539 bp) and sardine (N = 107; 425 bp). The mitochondrial DNA gene genealogies are shallow but diverse for both species. Haplotype frequencies are homogeneous among subpopulations, but genetic diversities peak for both species along Baja California and adjacent southern California. Mismatch distributions and Tajima's D-values reveal distinctive signatures of population bottlenecks and expansions. Sardine haplotypes coalesce at approximately 241,000 years bp, with an initial female effective population size Nf0 = 0 followed by exponential growth to Nf1 = 115 million. Anchovy haplotypes coalesce at approximately 282,000 years bp, with an initial population size of Nf0 = 14,000, followed by exponential growth to Nf1 = 2.3 million. These results indicate a founder event for sardine and a severe population decline for anchovy in the California Current during the late Pleistocene. Overall, these data support the basin model on decadal timescales, although local recruitment may dominate on shorter timescales.

Multiple cerebral abscesses as a complication of Mycobacterium fortuitum infection

Mycobacterium fortuitum is a rapidly growing, nontuberculous mycobacteria that has rarely been associated with central nervous system impairment. We describe the case of a patient who developed multiple cerebral abscesses revealing Mycobacterium fortuitum infection. Brain biopsy specimens showed suppurative, noncaseating, granulomatous inflammation consisting of epithelioid histiocytes and multinucleated giant cells. All clinical signs and CT scan cerebral lesions disappeared after institution of appropriate antimycobacterial therapy.

Blends of enteric and GIT-insoluble polymers used for film coating: physicochemical characterization and drug release patterns

THE OBJECTIVES OF THIS STUDY WERE: (i). to use blends of gastrointestinal tract (GIT)-insoluble and enteric polymers (ethyl cellulose and Eudragit L) as coating materials for multiparticulate controlled release dosage forms; (ii). to investigate the effects of the polymer blend ratio and coating level on the resulting drug release patterns; and (iii). to explain the observed phenomena based on the physicochemical properties of the systems. Propranolol HCl-loaded pellets were coated in a fluidized bed coater with organic polymer solutions; thin, drug-containing and drug-free, polymeric films were prepared using a casting knife. In vitro drug release, water uptake and dry weight loss studies were performed in 0.1 M HCl and phosphate buffer pH 7.4, respectively. The apparent drug diffusion coefficients within the polymeric systems were determined using different experimental and theoretical techniques (side-by-side diffusion cells, in vitro drug release from thin films; exact and approximate solutions of Fick's second law of diffusion). A broad range of drug release patterns from coated pellets could be achieved by varying the GIT-insoluble:enteric polymer blend ratio. With increasing relative amounts of Eudragit L, the release rates in both media significantly increased. The increase at low pH could be attributed to an increase in water uptake, as observed with thin films. Interestingly, only partial Eudragit L leaching occurred in phosphate buffer pH 7.4 even at high enteric polymer contents, indicating that the GIT-insoluble polymer effectively hindered the dissolution of the entrapped Eudragit L. At high pH, both polymer leaching and polymer swelling contributed to the control of drug release. The determined apparent drug diffusion coefficients take the two effects adequately into account.