Generic SFC-MS methodology for the quality control of vitamin D3 oily formulations

Vitamin D₃ is a key micronutrient whose intakes are inadequate for most populations worldwide. Supplementation with medicines or food supplements is commonly prescribed to correct this imbalance and the quality of these products must be ensured. In this context, a generic methodology for the assay of vitamin D₃ in oily formulations is proposed using supercritical fluid chromatography coupled to mass spectrometry (SFC-MS). It is in line with green analytical chemistry principles and combines the use of i) a fast and robust analytical method (4.0 min analysis time) ii) an easy sample preparation compatible with high throughput analysis ("dilute-and-shoot" approach) and iii) a relevant control strategy. Seventeen products from multiple manufacturers and encompassing a large content range were evaluated in this study. They were classified in four groups to streamline their processing considering the use of a matrix-matched calibration procedure. Matrix effect was thoroughly studied and was found to be low (99-106%), stable intra/inter-series and comparable between the different groups and types of matrices. The implemented control strategy was based on a three-level system suitability tests (SST). Level 1 SST: resolution of the critical pair that was above 1.5 for all analysis series. Level 2 SST: evaluation of the adequacy of the calibration for a QC sample in terms of recovery that was between 97% and 104% with a variability between 1% and 2%. Level 3 SST: method trueness that was between 95% and 102%. Sample analysis highlighted differences in types of products and dosage forms. This is the first study to propose a complete strategy for the quality control of vitamin D₃ oily formulations and should prove useful in QC laboratories.

Melatonin and osmoregulation in fish: A focus on Atlantic salmon Salmo salar smoltification

Part of the life cycle of several fish species includes important salinity changes, as is the case for the sea bass (Dicentrarchus labrax) or the Atlantic salmon (Salmo salar). Salmo salar juveniles migrate downstream from their spawning sites to reach seawater, where they grow and become sexually mature. The process of preparation enabling juveniles to migrate downstream and physiologically adapt to seawater is called smoltification. Daily and seasonal variations of photoperiod and temperature play a role in defining the timing of smoltification, which may take weeks to months, depending on the river length and latitude. Smoltification is characterised by a series of biochemical, physiological and behavioural changes within the neuroendocrine axis. This review discusses the current knowledge and gaps related to the neuroendocrine mechanisms that mediate the effects of light and temperature on smoltification. Studies performed in S. salar and other salmonids, as well as in other species undergoing important salinity changes, are reviewed, and a particular emphasis is given to the pineal hormone melatonin and its possible role in osmoregulation. The daily and annual variations of plasma melatonin levels reflect corresponding changes in external photoperiod and temperature, which suggests that the hormonal time-keeper melatonin might contribute to controlling smoltification. Here, we review studies on (i) the impact of pinealectomy and/or melatonin administration on smoltification; (ii) melatonin interactions with hormones involved in osmoregulation (e.g., prolactin, growth hormone and cortisol); (iii) the presence of melatonin receptors in tissues involved in osmoregulation; and (iv) the impacts of salinity changes on melatonin receptors and circulating melatonin levels. Altogether, these studies show evidence indicating that melatonin interacts with the neuroendocrine pathways controlling smoltification, although more information is needed to clearly decipher its mechanisms of action.

IRMPD spectroscopy and quantum chemistry calculations on mono- and bi-metallic complexes of acetylacetonate ligands with aluminum, iron, and ruthenium ions

Metal-ligand cluster ions are structurally characterized by means of gas-phase infrared multiple photon dissociation spectroscopy. The mass-selected complexes consist of one or two metal cations M³⁺ (M = Al, Fe, or Ru) and two to five anionic bidentate acetylacetonate ligands. Experimental IR spectra are compared with different density functional theory calculations, namely, PBE/TZVP, B3LYP/6-31G^*, and M06/6-31+G^**. Frequency analysis was also performed at different levels, namely, scaled static harmonic and unscaled static anharmonic, or with ab initio molecular dynamics simulations at the PBE/TZVP level. All methods lead to simulated spectra that fit rather well with experimental data, and the spectral red shifts of several main bands, in the 1200 cm^-1-1800 cm^-1 range, are sensitive to the strength of the metal-ligand interaction and to the spin state of the ion. Due to the rigidity of those complexes, first principles molecular dynamics calculations provide spectra similar to that produced by static calculations that are already able to catch the main spectral signatures using harmonic calculations at the B3LYP/6-31G^* level.

The Moovis® implant for trapeziometacarpal osteoarthritis: results after 2 to 6 years

In this retrospective study we reviewed the outcomes of 46 trapeziometacarpal joint replacements with the Moovis® prosthesis in 46 patients with painful osteoarthritis. The dual mobility design of this prosthesis aims to reduce prosthetic dislocation and subsidence. At follow-up 2 to 6 years (mean 5 years) after operation, pain was reduced from 6 to 0 on a visual analogue scale from 0 to 10. The scores of the Quick Disabilities of the Arm, Shoulder and Hand questionnaire improved significantly. Thumb motion and grip and pinch strength did not differ significantly from the contralateral hand. There were no radiographical signs of implant subsidence or loosening. No implant required revision. Forty-five patients rated the result as excellent or good. We conclude the Moovis® is a reliable and effective implant at short- to mid-term follow-up. Level of evidence: IV.

Performance evaluation of a MIP for the MISPE-LC determination of p-[18F]MPPF and a potential metabolite in human plasma

Within the family of serotonin (5-HT) receptors, the 5-HT_1A subtype is particularly interesting as it may be involved in various physiological processes or psychological disorders. The p-[¹⁸F]MPPF, a highly selective 5-HT_1A antagonist, is used for in vivo studies in human or animal by means of positron emission tomography (PET) [1]. In order to selectively extract p-[¹⁸F]MPPF and its main metabolites from plasma, molecularly imprinted polymer (MIP) was prepared against these compounds by using the p-MPPF as template. For the control of the selectivity, non-imprinted polymer (NIP) was also synthesized without template. The MIP sorbent, packed in disposable extraction cartridges (DECs), was then evaluated as molecularly imprinted solid-phase extraction (MISPE) prior to the LC determination. The conditions of extraction were evaluated in order to obtain the highest selective retention of the p-[¹⁸F]MPPF and its metabolites on this MIP. The MIP selectivity was exploited in the loading and washing steps by adjusting the pH of plasma samples at a suitable value and by selecting mixtures for the washing step to limit the contribution of non-specific interactions. Other important parameters involved in the conditioning and elution steps were also studied. Finally, a pre-validation was carried out with optimal extraction conditions to demonstrate the performance of this MISPE-LC method as a generic method in the context of evaluation of new MISPE for p-[¹⁸F]MPPF and its potential for metabolites extraction from human plasma.

The conventional protocol vs. a protocol including illumination with a fabric-based biophotonic device (the Phosistos protocol) in photodynamic therapy for actinic keratosis: a randomized, controlled, noninferiority clinical study

BACKGROUND

Topical photodynamic therapy (PDT) using methyl aminolaevulinate is a noninvasive treatment option suitable to treat clinical and subclinical actinic keratosis (AK) over a large area (field cancerization). The most widely used, conventional protocol in Europe includes illumination with a red-light lamp. This illumination commonly causes pain, and patients often cannot complete the treatment.

OBJECTIVES

The aims of this paper are twofold. The first aim is to introduce a novel protocol, the Phosistos protocol (P-PDT), which includes illumination with a fabric-based biophotonic device. The second and major aim is to assess the noninferiority, in terms of efficacy for PDT of AK, of P-PDT compared with the conventional protocol (C-PDT).

METHODS

A randomized, controlled, multicentre, intraindividual clinical study was conducted. Forty-six patients with grade I-II AK of the forehead and scalp were treated with P-PDT on one area (280 AK lesions) and with C-PDT on the contralateral area (280 AK lesions). The primary end point was the lesion complete response (CR) rate at 3 months, with an absolute noninferiority margin of -10%. Secondary end points included pain scores, incidence of adverse effects and cosmetic outcome.

RESULTS

Three months following treatment, the lesion CR rate of P-PDT was noninferior to that of C-PDT (79·3% vs. 80·7%, respectively; absolute difference -1·6%; one-sided 95% confidence interval -4·5% to infinity). The noninferiority of P-PDT to C-PDT in terms of the lesion CR rate remained at the 6-month follow-up (94·2% vs. 94·9%, respectively; absolute difference -0·6%; one-sided 95% confidence interval -2·7% to infinity). Moreover, the pain score at the end of illumination was significantly lower for P-PDT than for C-PDT (mean ± SD 0·3 ± 0·6 vs. 7·4 ± 2·3; P < 0·001).

CONCLUSIONS

P-PDT is noninferior to C-PDT in terms of efficacy for treating AK of the forehead and scalp and resulted in much lower pain scores and fewer adverse effects. What's already known about this topic? Topical photodynamic therapy using methyl aminolaevulinate is effective for treating actinic keratosis. In Europe, the conventional protocol involves illumination with a red-light lamp. Unfortunately, pain is often experienced by patients undergoing this protocol. An alternative protocol that uses daylight illumination has recently been shown to be as effective as the conventional protocol while being nearly painless. However, this alternative protocol can be conducted only in suitable weather conditions. What does this study add? The Phosistos protocol is demonstrated to be as effective as the conventional protocol, nearly as painless as the daylight protocols and suitable year round for treatment of actinic keratosis.

Vibronic spectra of protonated hydroxypyridines: contributions of prefulvenic and planar structures

The UV photofragmentation spectra of cold protonated hydroxypyridines display well resolved vibrational structures, interpreted with calculations at the CC2 level.

Impact of a pilot team on patients' pain reduction and satisfaction in an emergency department: A before-and-after observational study

BACKGROUND

Pain management and patient satisfaction were targeted in the emergency department of a Paris university hospital. In 1999, 77.0% of patients complained of pain on arrival and more than half of patients did not experience pain relief at discharge. The purpose of the study was to evaluate the outcomes of the implementation of a team piloting pain management on pain reduction and pain care satisfaction.

METHOD

Two cross-sectional surveys (04/10/1999 to 19/10/1999 and 03/04/2007 to 18/04/2007) were conducted before and after a team piloting pain management was deployed in the emergency department. Consecutive patients age 18 years and older who visited the department suffering from pain were given structured questionnaires that validated scales scoring pain upon arrival and at discharge. Patients' files were analyzed using structured forms. The parameters associated with pain reduction and patient satisfaction were sought.

RESULTS

In 2007, 65.0% of patients had their pain relieved vs. 35.1% in 1999 (P<0.001); 60.2% were satisfied with the pain care received vs. 39.8%. Pain management (e.g. waiting time ≤ 20 min: 47.6% vs. 20.8%; interventions on pain before the physician's examination: 63.0% vs. 13.8%; and pain reassessment after intervention: 13.8% vs. 4.5%) improved. Both pain reduction and patient satisfaction were significantly associated with intervention before the physician's examination. Pain reduction was independently and positively associated with time of survey, triage level (depending on the severity of their condition), pain intensity on arrival, and negatively associated with discharge without hospitalization. Satisfaction was independently and positively associated with waiting time before examination (0-20 min) and the absence of procedural pain.

CONCLUSION

The implementation of a team piloting pain management seemed to have had positive effects on pain management in the emergency department. However, respectively, 56.2% and 39.8% of patients remained without pain relief and dissatisfied with pain management at the end of their visit.

Observational Study of a French and Belgian Multicenter Cohort of 23 Patients Diagnosed in Adulthood With Mevalonate Kinase Deficiency

The aim of this study was to describe the clinical and biological features of Mevalonate kinase deficiency (MKD) in patients diagnosed in adulthood. This is a French and Belgian observational retrospective study from 2000 to 2014. To constitute the cohort, we cross-check the genetic and biochemical databases. The clinical, enzymatic, and genetic data were gathered from medical records. Twenty-three patients were analyzed. The mean age at diagnosis was 40 years, with a mean age at onset of symptoms of 3 years. All symptomatic patients had fever. Febrile attacks were mostly associated with arthralgia (90.9%); lymphadenopathy, abdominal pain, and skin lesions (86.4%); pharyngitis (63.6%); cough (59.1%); diarrhea, and hepatosplenomegaly (50.0%). Seven patients had psychiatric symptoms (31.8%). One patient developed recurrent seizures. Three patients experienced renal involvement (13.6%). Two patients had angiomyolipoma (9.1%). All but one tested patients had elevated serum immunoglobulin (Ig) D level. Twenty-one patients had genetic diagnosis; most of them were compound heterozygote (76.2%). p.Val377Ile was the most prevalent mutation. Structural articular damages and systemic AA amyloidosis were the 2 most serious complications. More than 65% of patients displayed decrease in severity and frequency of attacks with increasing age, but only 35% achieved remission. MKD diagnosed in adulthood shared clinical and genetic features with classical pediatric disease. An elevated IgD concentration is a good marker for MKD in adults. Despite a decrease of severity and frequency of attacks with age, only one-third of patients achieved spontaneous remission.

Intraspecific genetic admixture and the morphological diversification of an estuarine fish population complex

The North-east American Rainbow smelt (Osmerus mordax) is composed of two glacial races first identified through the spatial distribution of two distinct mtDNA lineages. Contemporary breeding populations of smelt in the St. Lawrence estuary comprise contrasting mixtures of both lineages, suggesting that the two races came into secondary contact in this estuary. The overall objective of this study was to assess the role of intraspecific genetic admixture in the morphological diversification of the estuarine rainbow smelt population complex. The morphology of mixed-ancestry populations varied as a function of the relative contribution of the two races to estuarine populations, supporting the hypothesis of genetic admixture. Populations comprising both ancestral mtDNA races did not exhibit intermediate morphologies relative to pure populations but rather exhibited many traits that exceeded the parental trait values, consistent with the hypothesis of transgressive segregation. Evidence for genetic admixture at the level of the nuclear gene pool, however, provided only partial support for this hypothesis. Variation at nuclear AFLP markers revealed clear evidence of the two corresponding mtDNA glacial races. The admixture of the two races at the nuclear level is only pronounced in mixed-ancestry populations dominated by one of the mtDNA lineages, the same populations showing the greatest degree of morphological diversification and population structure. In contrast, mixed-ancestry populations dominated by the alternate mtDNA lineage showed little evidence of introgression of the nuclear genome, little morphological diversification and little contemporary population genetic structure. These results only partially support the hypothesis of transgressive segregation and may be the result of the differential effects of natural selection acting on admixed genomes from different sources.

Landscape variability explains spatial pattern of population structure of northern pike (Esox lucius) in a large fluvial system

A growing number of studies have been investigating the influence of contemporary environmental factors on population genetic structure, but few have addressed the issue of spatial patterns in the variable intensity of factors influencing the extent of population structure, and particularly so in aquatic ecosystems. In this study, we document the landscape genetics of northern pike (Esox lucius), based on the analysis of nearly 3000 individuals from 40 sampling sites using 22 microsatellites along the Lake Ontario - St. Lawrence River system (750 km) that locally presents diverse degrees of interannual water level variation. Genetic structure was globally very weak (F ST = 0.0208) but spatially variable with mean level of differentiation in the upstream section of the studied area being threefold higher (F ST = 0.0297) than observed in the downstream sector (F ST = 0.0100). Beside interannual water level fluctuation, 19 additional variables were considered and a multiple regression on distance matrices model (R (2)  = 0.6397, P < 0.001) revealed that water masses (b = 0.3617, P < 0.001) and man-made dams (b = 0.4852, P < 0.005) reduced genetic connectivity. Local level of interannual water level stability was positively associated to the extent of genetic differentiation (b = 0.3499, P < 0.05). As water level variation impacts on yearly quality and localization of spawning habitats, our study illustrates how temporal variation in local habitat availability, caused by interannual water level fluctuations, may locally decrease population genetic structure by forcing fish to move over longer distances to find suitable habitat. This study thus represents one of the rare examples of how environmental fluctuations may influence spatial variation in the extent of population genetic structure within a given species.

Gas-phase structure of amyloid-β (12-28) peptide investigated by infrared spectroscopy, electron capture dissociation and ion mobility mass spectrometry

The gas-phase structures of doubly and triply protonated Amyloid-β12-28 peptides have been investigated through the combination of ion mobility (IM), electron capture dissociation (ECD) mass spectrometry, and infrared multi-photon dissociation (IRMPD) spectroscopy together with theoretical modeling. Replica-exchange molecular dynamics simulations were conducted to explore the conformational space of these protonated peptides, from which several classes of structures were found. Among the low-lying conformers, those with predicted diffusion cross-sections consistent with the ion mobility experiment were further selected and their IR spectra simulated using a hybrid quantum mechanical/semiempirical method at the ONIOM DFT/B3LYP/6-31 g(d)/AM1 level. In ECD mass spectrometry, the c/z product ion abundance (PIA) has been analyzed for the two charge states and revealed drastic differences. For the doubly protonated species, N - Cα bond cleavage occurs only on the N and C terminal parts, while a periodic distribution of PIA is clearly observed for the triply charged peptides. These PIA distributions have been rationalized by comparison with the inverse of the distances from the protonated sites to the carbonyl oxygens for the conformations suggested from IR and IM experiments. Structural assignment for the amyloid peptide is then made possible by the combination of these three experimental techniques that provide complementary information on the possible secondary structure adopted by peptides. Although globular conformations are favored for the doubly protonated peptide, incrementing the charge state leads to a conformational transition towards extended structures with 310- and α-helix motifs.

Pelagic life and depth: coastal physical features in West Africa shape the genetic structure of the Bonga Shad, Ethmalosa fimbriata

The bonga shad, Ethmalosa fimbriata, is a West African pelagic species still abundant in most habitats of its distribution range and thought to be only recently affected by anthropogenic pressure (habitat destruction or fishing pressure). Its presence in a wide range of coastal habitats characterised by different hydrodynamic processes, represents a case study useful for evaluating the importance of physical structure of the west African shoreline on the genetic structure of a small pelagic species. To investigate this question, the genetic diversity of E. fimbriata was assessed at both regional and species range scales, using mitochondrial (mt) and nuclear DNA markers. Whereas only three panmictic units were identified with mtDNA at the large spatial scale, nuclear genetic markers (EPIC: exon-primed intron-crossing) indicated a more complex genetic pattern at the regional scale. In the northern-most section of shad’s distribution range, up to 4 distinct units were identified. Bayesian inference as well as spatial autocorrelation methods provided evidence that gene flow is impeded by the presence of deep-water areas near the coastline (restricting the width of the coastal shelf), such as the Cap Timiris and the Kayar canyons in Mauritania and Senegal, respectively. The added discriminatory power provided by the use of EPIC markers proved to be essential to detect the influence of more subtle, contemporary processes (e.g. gene flow, barriers, etc.) acting within the glacial refuges identified previously by mtDNA.

Invasion dynamics of a fish-free landscape by brown trout (Salmo trutta)

Metapopulation dynamics over the course of an invasion are usually difficult to grasp because they require large and reliable data collection, often unavailable. The invasion of the fish-free freshwater ecosystems of the remote sub-Antarctic Kerguelen Islands following man-made introductions of brown trout (Salmo trutta) in the 1950's is an exception to this rule. Benefiting from a full long term environmental research monitoring of the invasion, we built a Bayesian dynamic metapopulation model to analyze the invasion dynamics of 85 river systems over 51 years. The model accounted for patch size (river length and connections to lakes), alternative dispersal pathways between rivers, temporal trends in dynamics, and uncertainty in colonization date. The results show that the model correctly represents the observed pattern of invasion, especially if we assume a coastal dispersal pathway between patches. Landscape attributes such as patch size influenced the colonization function, but had no effect on propagule pressure. Independently from patch size and distance between patches, propagule pressure and colonization function were not constant through time. Propagule pressure increased over the course of colonization, whereas the colonization function decreased, conditional on propagule pressure. The resulting pattern of this antagonistic interplay is an initial rapid invasion phase followed by a strong decrease in the invasion rate. These temporal trends may be due to either adaptive processes or environmental gradients encountered along the colonization front. It was not possible to distinguish these two hypotheses. Because invasibility of Kerguelen Is. freshwater ecosystems is very high due to the lack of a pre-existing fish fauna and minimal human interference, our estimates of invasion dynamics represent a blueprint for the potential of brown trout invasiveness in pristine environments. Our conclusions shed light on the future of polar regions where, because of climate change, fish-free ecosystems become increasingly accessible to invasion by fish species.

The supinator muscle: anatomical bases for deep branch of the radial nerve entrapment

PURPOSE

Our goals were to carry out an anatomical description of the internal architecture of the supinator muscle in order to describe potentially compressive structures for the deep branch of the radial nerve (DBRN) and to establish reference landmarks for the surgical treatment of radial tunnel syndrome.

METHODS

Thirty upper limbs were dissected. The pennation angle of proximal and distal arcades of the supinator to the radial shaft axis was measured. Possible compressive structures of both superficial and deep heads of supinator were recorded. Proximal and distal arcades of the superficial layer of the supinator were classified according to their fiber content as tendinous, musculo-tendinous, muscular or membranous. The distances of superficial layer of the supinator muscle to the humeroradial joint line and lateral epicondyle were measured.

RESULTS

Pennation angle was 33.6° (±4.2°) for the superficial layer and 50.2° (±6.6°) for the deep layer. The difference was statistically significant (p < 0.0001). The proximal arcade was purely tendinous in 20 cases (66.7 %). The distal arcade was mainly tendinous or musculo-tendinous (70 %). The average distance between the lateral epicondyle and the proximal arcade was 41.6 mm. We did not find any other potentially compressive structure within DBRN course between both layers.

CONCLUSION

Our anatomical results about pennation angle could be used as a basis for a thorough functional study about the supinator. Both proximal and distal arcades appeared as the two zones ables to compress the DBRN. Their localization should help the surgeon for the DBRN neurolysis.

Development of a nano-liquid chromatography on chip tandem mass spectrometry method for high-sensitivity hepcidin quantitation

Microfluidic LC systems present undeniable advantages over classical LC in terms of sensitivity. Hepcidin, a peptide marker of clinical disorders linked to iron metabolism, was used as model to demonstrate peptide quantification potentialities of LC-chip coupled to a nanoelectrospray source ion trap mass spectrometer in an aqueous sample. First, stable isotope labelled hepcidin was chosen as internal standard and gradient as well as sample compositions were optimised using design of experiments as development tool. The method was then prevalidated using accuracy profiles in order to select the most appropriate response function and to confirm the ability of the technique to quantify low hepcidin concentration. A reliable and very sensitive quantitation method was finally obtained using this integrated microfluidic technology. Indeed, good results with respect to accuracy, trueness and precision were achieved, as well as a very low limit of quantitation (0.07 ng/ml). Method suitability of nano-LC on chip tandem mass spectrometry for hepcidin quantitation was also demonstrated in complex media such as human plasma.

Slow photoelectron spectroscopy of δ-valerolactam and its dimer

We studied the single-photon ionization of gas-phase δ-valerolactam (piperidin-2-one) and of its dimer using vacuum-ultraviolet (VUV) synchrotron radiation coupled to a velocity map imaging electron/ion coincidence spectrometer. The slow photoelectron spectrum (SPES) of the monomer is dominated by the vibrational transitions to the ͠X state. Moreover, several weaker and complex bands are observed, corresponding to the population of the vibrational bands (pure or combination) of the electronically excited states of the cation arising from their mutual vibronic interactions. For the dimer, we measure a unique large band. These spectra are assigned with the help of theoretical calculations dealing with the equilibrium geometries, electronic-state patterns and evolutions, harmonic and anharmonic wavenumbers of the monomer and dimer, either neutral or positively charged. The state energies of the [δ-valerolactam](+) cation in the ͠X ground, ͠A, ͠B, ͠C, excited electronic states, and of the [δ-valerolactam](2) (+) cation's lowest states are determined. After its formation, [δ-valerolactam](2) (+) is subject to intramolecular isomerization, H transfer and then unimolecular fragmentation processes. Close to the ionization thresholds, the photoionization of these molecules is found to be mainly dominated by a direct process whereas the indirect route (autoionization) contributes at higher energies.

Liposome surface charge influence on skin penetration behaviour

Vesicular systems have shown their ability to increase dermal and transdermal drug delivery. Their mechanism of drug transport into and through the skin has been investigated but remains a much debated question. Several researchers have outlined that drug penetration can be influenced by modifying the surface charge of liposomes. In the present work we study the influence of particle surface charge on skin penetration. The final purpose is the development of a carrier system which is able to enhance the skin delivery of two model drugs, betamethasone and betamethasone dipropionate. Liposomes were characterised by their size, morphology, zeta potential, encapsulation efficiency and stability. Ex vivo diffusion studies using Franz diffusion cells were performed. Confocal microscopy was performed to visualise the penetration of fluorescently labelled liposomes into the skin. This study showed the potential of negatively charged liposomes to enhance the skin penetration of betamethasone and betamethasone dipropionate.

[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.