Evaluation of utero-placental vascularization using contrast-enhanced ultrasound: Early first trimester maternal perfusion of the intervillous space is confirmed

INTRODUCTION

The objective was to confirm and semiquantify the maternal perfusion of the intervillous space between 8 and 13 + 6 gestational weeks (GW).

METHODS

We conducted a prospective, multicenter, and nonrandomized open study. Women undergoing voluntary termination of pregnancy at three different gestational ages (Group 8 GW: 8 to 8 + 6 GW, Group 11GW: 11 to 11 + 6 GW and Group 13GW: 13 to 13 + 6 GW) were included, with 14 subjects per group. Women presenting with a personal risk of preeclampsia and/or intrauterine growth restriction were excluded. Contrast-enhanced ultrasound (CEUS) was performed with an intravenous bolus administration of 2.4 mL of microbubbles. The region of interest (ROI) was the entire placenta. The perfusion curves and kinetic parameters, including wash-in perfusion index, peak enhancement and mean transit time, were calculated.

RESULTS

Of the 42 women initially included, interpretable perfusion curves could be obtained for 33. Regardless of the gestational age, contrast was observed in the entire placenta. No significant difference in perfusion parameters was observed between groups. There was an association between signal intensity and both maternal heart frequency and placental location. Signal intensity was decreased when the heart frequency increased (p < 0.05) and when the placenta was in a nonanterior position (p > 0.005).

DISCUSSION

We confirmed the presence of maternal perfusion of the intervillous space as early as 8 GW. No significant increase in perfusion parameters was observed between 8 and 13 + 6 GW. Our observations, in accordance with the previous experiment published by Roberts et al.1, strongly challenge the classic trophoblastic plug theory.

Chemical vapor deposition (DLI-CVD) and characterization of multiphasic molybdate-based catalysts for propene oxidation

Deposition by DLI-CVD of a multi-element BiFeCoMo catalyst in the millimetric channels of a monolithic reactor has been achieved. When tested for the oxidation of propene to acrolein the reactors with various coatings are efficient but need to be optimized.

[Evaluation of cardiac MRI in the follow up assessment of patients with pulmonary arterial hypertension]

Haemodynamic follow up in pulmonary arterial hypertension (PAH) is currently based on right heart catheterisation (RHC). The primary objective of the EVITA study is to compare the use of cardiac magnetic resonance imaging (cMRI) with RHC in the identification of an unfavourable hemodynamic status. The secondary objectives are to determine the role of cMRI in the follow up process. Patients will undergo at diagnosis and at follow up visits both RHC and cMRI. Patients will be followed and treated according to the current guidelines. The primary endpoint will be an unfavourable haemodynamic status defined by cardiac index<2.5L/min/m² or a right atrial pressure≥8mm Hg measured with RHC compared with a cardiac index<2.5L/min/m² or right ventricle ejection fraction<35% or an absolute decrease of 10% from the previous measurement with cMRI. Exact values of sensitivity, specificity and 95% confidence intervals will be computed. A population of 180 subjects will have a power of 90% with an α risk of 5%. Univariate and multivariate Cox analysis will allow answering to the secondary objectives. We expect to demonstrate that cMRI could be partly used instead of RHC in the follow up of patients with PAH.

Evaluation of the clinical benefit of an electromagnetic navigation system for CT-guided interventional radiology procedures in the thoraco-abdominal region compared with conventional CT guidance (CTNAV II): study protocol for a randomised controlled trial

BACKGROUND

Interventional radiology includes a range of minimally invasive image-guided diagnostic and therapeutic procedures that have become routine clinical practice. Each procedure involves a percutaneous needle insertion, often guided using computed tomography (CT) because of its availability and usability. However, procedures remain complicated, in particular when an obstacle must be avoided, meaning that an oblique trajectory is required. Navigation systems track the operator's instruments, meaning the position and progression of the instruments are visualised in real time on the patient's images. A novel electromagnetic navigation system for CT-guided interventional procedures (IMACTIS-CT®) has been developed, and a previous clinical trial demonstrated improved needle placement accuracy in navigation-assisted procedures. In the present trial, we are evaluating the clinical benefit of the navigation system during the needle insertion step of CT-guided procedures in the thoraco-abdominal region.

METHODS/DESIGN

This study is designed as an open, multicentre, prospective, randomised, controlled interventional clinical trial and is structured as a standard two-arm, parallel-design, individually randomised trial. A maximum of 500 patients will be enrolled. In the experimental arm (navigation system), the procedures are carried out using navigation assistance, and in the active comparator arm (CT), the procedures are carried out with conventional CT guidance. The randomisation is stratified by centre and by the expected difficulty of the procedure. The primary outcome of the trial is a combined criterion to assess the safety (number of serious adverse events), efficacy (number of targets reached) and performance (number of control scans acquired) of navigation-assisted, CT-guided procedures as evaluated by a blinded radiologist and confirmed by an expert committee in case of discordance. The secondary outcomes are (1) the duration of the procedure, (2) the satisfaction of the operator and (3) the irradiation dose delivered, with (4) subgroup analysis according to the expected difficulty of the procedure, as well as an evaluation of (5) the usability of the device.

DISCUSSION

This trial addresses the lack of published high-level evidence studies in which navigation-assisted CT-guided interventional procedures are evaluated. This trial is important because it addresses the problems associated with conventional CT guidance and is particularly relevant because the number of interventional radiology procedures carried out in routine clinical practice is increasing.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT01896219 . Registered on 5 July 2013.

Enhanced performance of electrospun carbon fibers modified with carbon nanotubes: promising electrodes for enzymatic biofuel cells

New nanostructured electrodes, promising for the production of clean and renewable energy in biofuel cells, were developed with success. For this purpose, carbon nanofibers were produced by the electrospinning of polyacrylonitrile solution followed by convenient thermal treatments (stabilization followed by carbonization at 1000, 1200 and 1400° C), and carbon nanotubes were adsorbed on the surfaces of the fibers by a dipping method. The morphology of the developed electrodes was characterized by several techniques (SEM, Raman spectroscopy, electrical conductivity measurement). The electrochemical properties were evaluated through cyclic voltammetry, where the influence of the carbonization temperature of the fibers and the beneficial contribution of the carbon nanotubes were observed through the reversibility and size of the redox peaks of K3Fe(CN)6 versus Ag/AgCl. Subsequently, redox enzymes were immobilized on the electrodes and the electroreduction of oxygen to water was realized as a test of their efficiency as biocathodes. Due to the fibrous and porous structure of these new electrodes, and to the fact that carbon nanotubes may have the ability to promote electron transfer reactions of redox biomolecules, the new electrodes developed were capable of producing higher current densities than an electrode composed only of electrospun carbon fibers.

[Acute adrenal insufficiency due to bilateral adrenal hematoma following severe thrombopenia induced by low-molecular-weight heparin]

BACKGROUND

Bilateral adrenal hematoma is an uncommon cause of acute adrenal insufficiency. An association with thrombopenia induced by low-molecular-weight heparin even more so. Diagnosis is difficult as the clinical manifestations mimic septic shock.

CASE REPORT

A 63-year-old woman developed acute adrenal insufficiency due to bilateral adrenal hematoma following severe thrombopenia induced by low-molecular-weight heparin prescribed after an orthopedic operation. Outcome was favorable.

CONCLUSION

Acute adrenal insufficiency must be entertained as a possible diagnosis in patients with heparin-induced thrombopenia.

Clonal relationships among Escherichia coli serogroup 06 isolates from human and animal infections

The clonal relationship of thirty E. coli strains of 0 antigen serotype 06 isolated from human, dog, pig or cow infections were investigated. Two main clones with serotypes 06 : H1 or 06 : H31, H- were identified. Isolates from humans, dogs, pigs and cows were found in both clones, indicating that animals are a possible source for human extraintestinal Escherichia coli strains. Two human ETEC (06 : H16) and two pig isolates (06 : H10) were not related to the 06 : H1 or 06 : H31, H- E. coli clones.

Factors and markers of virulence in Escherichia coli from human septicemia

One hundred Escherichia coli isolates from human septicemia were characterized with respect to O serogroups 1, 2, 4, 6, 7, 8, 15, 18, 75 and 78, alpha-hemolysin, carboxylesterase B typing, cytotoxic necrotizing factor, F165 and CS31A fimbrial antigens, aerobactin production, colicins, and antibiotic sensitivity. A factorial analysis of correspondence and chi 2 tests indicated that most of E. coli isolates belonging to the studied O serogroups were positive for the virulence factors or markers alpha-haemolysin, carboxylesterase B2 type, cytotoxic necrotizing factor, F165 fimbrial antigen and were antibiotic-sensitive (Group I). These characteristics differentiated them from E. coli isolates from other O serogroups which were generally antibiotic resistant and negative for the cited virulence factors and markers (Group II). Aerobactin and colicin production did not differentiate the two E. coli groups. E. coli O serogroups 4 and 6 were highly represented in group I and were responsible for most of the differences between the two groups.