Search

The composition of AMP and concentrations of samples are analyzed to study the inclusion complexes in solution of CD and AMP and the viscosity of these mixtures. The higher concentrations of these solutions show increased viscosity and large cluster formation and a significant response to UV and visible spectra which is not observed in the dilute solutions.

The Molopo Farms Complex is an extremely poorly exposed, major, ultramafic-mafic layered intrusion straddling the southern border of Botswana with South Africa. It lies within the south-western part of the ∼2.0 Ga large igneous province of southern and central Africa that includes the better known Bushveld Complex. Integrated interpretation of regional gravity data and new high- resolution airborne magnetic data have constrained the geometry of the Molopo Farms Complex in southern Botswana as a strongly faulted, polyphase intrusion compartmentalised by regional ductile shear zones. Previous models showing that the Complex was emplaced in at least two discrete stages are supported. Ultramafic rocks were initially emplaced as a semi-coherent lopolithic sheet up to about 4 km in thickness cutting across Transvaal Supergroup strata that had already been folded into open eastwest trending dome and basin structures with wavelengths of about 4 kin. Steeply dipping, dyke-like ultramafic bodies adjacent to, and within major shears are inferred to be solidified feeders to the mare lopolithic part of the MFC. It is likely that the initial ultramafic sheet was emplaced at a high crustal level (<3 km depth) into an attenuated Transvaal Supergroup sequence. This lack of a thick hanging wall sequence is thought to he significant for the emplacement of the succeeding mafic sheets. The ultramafic sheet thermally altered its wall rock and also created a complex fracture system in its hanging wall rocks. Differentiation within the ultramafic sheet produced basal harzburgites overlain by bronzites and possibly mafic sheets. Later mafic/basic sheets and dykes, again fed along shear-controlled, steeply dipping zones, spread into the fracture network created by the initial emplacement of the ultramafic lopolith to form a distinctive spider's-web pattern on high-resolution airborne magnetic maps. It is proposed that either post- emplacement regional folding or gravitational collapse of the basal ultramafic lopolith produced a major basin with a ∼40 km eastwest diameter, north of the Jwaneng-Makopong Shear Zone and smaller basin to the southeast. The newly postulated, steeply dipping ultramafic/mafic feeders, as well as the ultramafic lopolith and areas with anomalous nickel values in soils are considered to be prospective for PGE-bearing magmatic nickel-copper sulphide mineralisation. Magmatic rocks dated at about 2.0 Ga are a common feature, not only of the Kaapvaal Craton, but of all the African cratonic blocks south of the Equator. Reactivated intracratonic faults and shears appear to control emplacement of individual magmatic complexes although a sub-continental thermal anomaly unconfined by lithospheric plate boundaries is a likely driving force for the widespread magmatism. [ABSTRACT FROM AUTHOR]

The use of relaxometry and Diffusion-Tensor Imaging sequences for brain tumor assessment is limited by their long acquisition time. We aim to test the effect of a denoising algorithm based on a Deep Learning Reconstruction (DLR) technique on quantitative MRI parameters while reducing scan time. In 22 consecutive patients with brain tumors, DLR applied to fast and noisy MR sequences preserves the mean values of quantitative parameters (Fractional anisotropy, mean Diffusivity, T1 and T2-relaxation time) and produces maps with higher structural similarity compared to long duration sequences. This could promote wider use of these biomarkers in clinical setting., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial or personal relationships that could be viewed as influencing the work reported in this paper., (Copyright © 2023. Published by Elsevier Masson SAS.)

Objectives: To assess the feasibility and technical outcomes of pelvic bone cementoplasty using an electromagnetic navigation system (EMNS) in standard practice., Materials and Methods: Monocentric retrospective study of all consecutive patients treated with cementoplasty or reinforced cementoplasty of the pelvic bone with EMNS-assisted procedures. The endpoints were periprocedural adverse events, needle repositioning rates, procedure duration, and radiation exposure., Results: A detailed description of the technical steps is provided. Thirty-three patients (68 years ± 10) were treated between February 2016 and February 2020. Needle repositioning was required for 1/33 patients (3%). The main minor technical adverse event was soft tissue PMMA cement leaks. No major adverse event was noted. The median number of CT acquisitions throughout the procedures was 4 (range: 2 to 8). Radiation exposure and mean procedure duration are provided., Conclusion: Electromagnetic navigation system-assisted percutaneous interventions for the pelvic bone are feasible and lead to low rates of minor technical adverse events and needle repositioning. Procedure duration and radiation exposure were low., Key Points: • Initial experience for 33 patients treated with an electromagnetic navigation assistance for pelvic cementoplasty shows feasibility and safety. • The use of an electromagnetic navigation system does not expose to high procedure duration or radiation exposure. • The system is efficient in assisting the radiologist for extra-axial planes in challenging approaches., (© 2022. The Author(s), under exclusive licence to European Society of Radiology.)

Background and Purpose: Sturge-Weber syndrome is a rare congenital neuro-oculo-cutaneous disorder. Although the principal mechanism of Sturge-Weber syndrome is characterized by a leptomeningeal vascular malformation, few data regarding perfusion abnormalities of the brain parenchyma are available. Therefore, the aim of this study was to assess the diagnostic performance of arterial spin-labeling perfusion imaging in the early stage of Sturge-Weber syndrome before 1 year of age until 3.5 years of age. We hypothesized that a leptomeningeal vascular malformation has very early hypoperfusion compared with controls with healthy brains., Materials and Methods: We compared the CBF using arterial spin-labeling perfusion imaging performed at 3T MR imaging in the brain parenchymal regions juxtaposing the leptomeningeal vascular malformation in patients with Sturge-Weber syndrome ( n = 16; 3.5 years of age or younger) with the corresponding areas in age-matched controls with healthy brains ( n = 58). The analysis was performed following two complementary methods: a whole-brain voxel-based analysis and a visual ROI analysis focused on brain territory of the leptomeningeal vascular malformation., Results: Whole-brain voxel-based comparison revealed a significant unilateral decrease in CBF localized in the affected cortices of patients with Sturge-Weber syndrome ( P  < .001). CBF values within the ROIs in patients with Sturge-Weber syndrome were lower than those in controls (in the whole cohort: median, 25 mL/100g/min, versus 44 mL/100g/min; P  < .001). This finding was also observed in the group younger than 1 year of age, emphasizing the high sensitivity of arterial spin-labeling in this age window in which the diagnosis is difficult., Conclusions: Arterial spin-labeling perfusion imaging in the early stage of Sturge-Weber syndrome can help to diagnose the disease by depicting a cortical hypoperfusion juxtaposing the leptomeningeal vascular malformation., (© 2022 by American Journal of Neuroradiology.)

Purpose: Middle meningeal artery (MMA) embolization is emerging as a potential treatment of chronic subdural hematomas (CSDHs). The purpose of this study is to describe MMA angiographic anatomy in relation to CSDH embolization., Methods: This retrospective monocentric study was performed on imaging data of MMA embolization procedures for CSDH treatment performed between March 15, 2018 and April 30, 2020. Imaging data, including digital subtraction angiography (DSA) were reviewed independently by two physicians. Discrepancies were resolved by consensus. The MMA bifurcation pattern was analyzed according to an extended Adachi classification. Relations of the MMA with the ophthalmic artery (OA) were also analyzed., Results: In this study, 140 MMAs were analyzed. Dominance of the anterior branch (type I) was observed in only 57/140 (41%) MMAs with a moderate interobserver agreement for classifying MMA into type I against all other (κ = 0.53, 95% confidence interval, CI 0.39-0.67). The posterior branch presented a proximal origin (type A), at the point of emergence of the MMA from the foramen spinosum or its immediate vicinity, in 48/135 (36%) MMAs with a very good interobserver agreement for classifying MMAs into type A against all other (κ = 0.82, 95% CI 0.72-0.92). An angiographic relationship with the OA was observed in 26 MMAs (19%)., Conclusion: In the majority of CSDH patients both anterior and posterior branches of the MMA should be targeted to achieve extensive convexity devascularization. Frequent anatomical variations of the MMA with respect to emergence of the posterior branch and MMA orbital branches are expected to impact CSDH embolization strategy., (© 2021. Springer-Verlag GmbH, DE part of Springer Nature.)

Background and Purpose: Chronic subdural hematoma embolization, an apparently simple procedure, can prove to be challenging because of the advanced age of the target population. The aim of this study was to compare 2 arterial-access strategies, femoral versus patient-tailored CTA-based frontline access selection, in chronic subdural hematoma embolization procedures., Materials and Methods: This was a monocentric retrospective study. From the March 15, 2018, to the February 14, 2019 (period 1), frontline femoral access was used. Between February 15, 2019, and March 30, 2020 (period 2), the choice of the frontline access, femoral or radial, was based on the CTA recommended as part of the preoperative work-up during both above-mentioned periods. The primary end point was the rate of catheterization failure. The secondary end points were the rate of access site conversion and fluoroscopy duration., Results: During the study period, 124 patients (with 143 chronic subdural hematomas) underwent an embolization procedure (mean age, 74 [SD, 13] years). Forty-eight chronic subdural hematomas (43 patients) were included during period 1 and were compared with 95 chronic subdural hematomas (81 patients) during period 2. During the first period, 5/48 (10%) chronic subdural hematoma embolizations were aborted due to failed catheterization, significantly more than during period 2 (1/95, 1%; P  = .009). The rates of femoral-to-radial ( P  = .55) and total conversion ( P  = .86) did not differ between the 2 periods. No significant difference was found regarding the duration of fluoroscopy ( P  = .62)., Conclusions: A CTA-based patient-tailored choice of frontline arterial access reduces the rate of catheterization failure in chronic subdural hematoma embolization procedures., (© 2021 by American Journal of Neuroradiology.)

Chronic subdural hematomas (CSDHs) are one of the most prevalent head-trauma-related conditions. The middle meningeal artery (MMA) may participate in the pathophysiology of CSDHs. The aim of this study was to determine whether CSDHs are associated with large MMAs. Patients referred for CSDH embolization and having undergone a computed tomography angiography (CTA) before embolization were retrospectively included. For each CSDH patient, two age- and sex-matched controls with a CTA performed during the study period were selected. Size comparisons of the MMA were performed between MMAs ipsilateral to CSDHs, on the contralateral side, and in controls. Comparison was also made with angiographic measurements from CSDH embolization procedures. Seventy-five patients with CSDH with available CTAs prior to embolization were enrolled and 146 MMAs were measured. One hundred fifty controls were included and 288 MMAs were measured. The median diameter of the 94 MMAs ipsilateral to a CSDH (1.5 mm; interquartile range [IQR] 1.3-1.7) was significantly larger than that of control MMAs (1.28 mm; IQR 1.15-1.4) ( p  < 0.001). The median diameter of 52 MMAs on the side of a unilateral CSDH (1.6 mm; IQR 1.4-1.8) was larger than that of the 52 contralateral MMAs (1.4 mm; IQR 1.25-1.6) ( p  < 0.001). Among the characteristics of patients with CSDH, multiple surgeries were associated with significantly larger MMAs (>1.7 mm; p  = 0.01). MMAs ipsilateral to CSDHs appear to be significantly larger as compared with contralateral MMAs and MMAs in a control population, suggesting the involvement of the MMA in the pathophysiology of CSDH.

Background: Embolization of the middle meningeal artery (MMA) has emerged as a potential treatment of chronic subdural hematomas (CSDHs)., Objective: To evaluate the impact on recurrence rate of postsurgical embolization of CSDH in patients with a higher than average risk of recurrence., Methods: A monocentric retrospective study was performed on retrospectively collected data. From March 2018 to December 2019, embolization of the MMA was proposed as an adjunct postoperative treatment after burr-hole surgery in patients operated for a recurrent CSDH or a CSDH with an independent recurrence risk factor, including antiplatelet therapy, full anticoagulation therapy, coagulation disorder, hepatopathy, or chronic alcoholism. Patients who had undergone postoperative embolization were compared with a historic group of patients operated between March 2016 and March 2018, selected based on the same inclusion criteria., Results: During the study period, 89 patients (with 74 unilateral and 15 bilateral CSDHs) were included and underwent an embolization procedure, leading to 91 out of a total of 104 MMA being embolized (88%). These were compared with 174 patients (138 unilateral and 36 bilateral CSDH) in the historic control group. One major procedure-related adverse event was registered. Four of the 89 patients (4%) required surgery for a CSDH recurrence in the embolization group, significantly less than the 24 of 174 patients (14%) in the control group (OR=0.28, 95% CI 0.07 to 0.86, p=0.02)., Conclusions: Postsurgical embolization of the MMA may reduce the recurrence rate of CSDHs with a risk factor of recurrence., Competing Interests: Competing interests: FC reports conflict of interest (unrelated) with Medtronic, Guerbet, Balt Extrusion (payment for readings), Codman Neurovascular (core laboratory). N-AS is consultant for Medtronic, Balt Extrusion, Microvention. The other authors report no conflict of interest concerning the materials or methods used in this study or the findings specified in this paper. The manuscript is not supported by industry. ES is principal investigator of a randomized controlled trial related to chronic subdural hematomas embolization financed by a PHRC-IR public grant (non-related to the present study)., (© Author(s) (or their employer(s)) 2020. No commercial re-use. See rights and permissions. Published by BMJ.)

French program of breast cancer screening is implemented since15 years and results are in adequation with international guidelines except for participation. To answer to recurrent controversies about breast cancer screening, publications from National Institute of French cancer registry confirm the positive impact of screening on decreasing mortality for participating women. The harms of mammography (and not from screening) need to be communicated to the invited women to help them to make decision about participation but also the risk of worse prognosis in case of symptomatic cancer. The future of screening will be different and works are in progress to find new ways to select women who will beneficiate for screening and whose cancer needs to be treated. Until then, the only way to screen for breast cancer stays the mammographic process as well as other technics in case of dense breast or in case of family history of breast cancer., (Copyright © 2019 Société Française du Cancer. Published by Elsevier Masson SAS. All rights reserved.)

In this work, Taylor dispersion analysis and capillary electrophoresis were used to characterize the size and charge of polymeric drug delivery nanogels based on polyglutamate chains grafted with hydrophobic groups of vitamin E. The hydrophobic vitamin E groups self-associate in water to form small hydrophobic nanodomains that can incorporate small drugs or therapeutic proteins. Taylor dispersion analysis is well suited to determine the weight average hydrodynamic radius of nanomaterials and to get information on the size polydispersity of polymeric samples. The effective charge was determined either from electrophoretic mobility and hydrodynamic radius using electrophoretic modeling (three different approaches were compared), or by indirect UV detection in capillary electrophoresis. The influence of vitamin E hydrophobicity on the polymer effective charge has been studied. The presence of vitamin E leads to a drastic decrease in polymer effective charge in comparison to non-modified polyglutamate. Finally, the electrophoretic behavior of polyglutamate backbone grafted with hydrophobic vitamin E (pGVE) nanogels according to the ionic strength was investigated using the recently proposed slope plot approach. It was deduced that the pGVE nanogels behave electrophoretically as polyelectrolytes which is in good agreement with the high water content of the nanogels.

The authors report their experience of the systematic use of a monobloc pin-plate in fractures of the trochanteric region in the elderly. The review of a series of 100 cases with a mortality of 16% demonstrates that this technique ensures excellent results compared with other published series. The biomechanical reliability of the monobloc pin-plate allows immediate weight-bearing in all patients. The technical simplicity and the better preoperative preparation of elderly patients allows an improvement in the postoperative course and consequently in patient survival. This operative technique can be proposed routinely with no restrictions.