Intraoperative electron beam intercomparison of 6 sites using mailed thermoluminescence dosimetry: Absolute dose and energy.

PURPOSE: In 2018, the Netherlands Commission on Radiation Dosimetry subcommittee on IORT initiated a limited intercomparison of electron IORT (IOERT) in Belgium and The Netherlands. The participating institutions have enough variability in age, type of equipment, and in dose calibration protocols. METHODS: In this study, three types of IOERT-dedicated mobile accelerators were represented: Mobetron 2000, LIAC HWL and LIAC. Mobetron produces electron beams with energies of 6, 9 and 12 MeV, while LIAC HWL and LIAC can deliver 6, 8, 10 and 12 MeV electron beams. For all energies, the reference beam (10 cm diameter, 0° incidence) and 5 cm diameter beams were measured, as these smaller beams are used more frequently in clinic. The mailed TLD service from the Radiation Dosimetry Services (RDS, Houston, USA) has been used. Following RDS' standard procedures, each beam was irradiated to 300 cGy at dmax with TLDs around dmax and around depth of 50 % dose (R50). Absolute dose at 100 % and beam energy, expressed as R50, could be verified in this way. RESULTS: All absolute doses and energies under reference conditions were well within RDS-stated uncertainties: dose deviations were <5 % and deviations in R50 were <5 mm. For the small 5 cm beams, all results were also within acceptance levels except one absolute dose value. Deviations were not significantly dependent on manufacturer, energy, diameter and calibration protocol. CONCLUSIONS: All absolute dose values, except one of a non-reference beam, and all energy values were well within the measurement accuracy of RDS TLDs.

Correction: Krayem et al. The Benefit of Reactivating p53 under MAPK Inhibition on the Efficacy of Radiotherapy in Melanoma. Cancers 2019, 11, 1093.

In the original article [...].

Interest of a new large diffusive gradients in thin films (L-DGT) for organic compounds monitoring: On-field comparison with conventional passive samplers.

In this work, the performances of a Large Diffusive Gradients in Thin films (L-DGT, i.e., a DGT based on a Chemcatcher® holder with a 5-fold larger sampling area) were compared on-field with the conventional DGT and the Polar Organic Chemical Integrative Sampler (POCIS) for the monitoring of a wide range of organic contaminants (i.e., 65 pesticides and metabolites, 53 pharmaceuticals and 12 hormones). These three passive samplers were simultaneously deployed in four rivers during 14 days. Their performances were then evaluated according to their detection and quantification capacities and their physical robustness. The results obtained confirm the advantages of the L-DGT over the conventional DGT regarding its sensitivity but also its robustness during field deployment. The POCIS provides the higher sensitivity, allowing the detection of more organic compounds compared to the DGT and, to a lesser extent, the L-DGT. However, both L-DGT and DGT reduces the uncertainty on the determination of the time-weighted average concentrations (CW), mainly due to the narrow range of variation of their calibration parameters. Indeed, for a given compound, CW can vary up to only a 3-fold factor with DGT and L-DGT compared to a 2 to 10-fold factor (up to 50) with POCIS. Thus, the L-DGT appears to be more suitable than DGT in low-contaminated contexts, which require higher sensitivity, or than POCIS when a CW determination is needed. For a qualitative evaluation however, the POCIS remains the most suitable passive sampler.

Embolization before Gamma Knife radiosurgery for cerebral arteriovenous malformations does not negatively impact its obliteration rate: a series of 190 patients.

PURPOSE: Embolization of arteriovenous malformations (AVMs) before radiosurgery has been reported to negatively impact the obliteration rate. This study aims to assess treatment outcomes in a series of 190 patients treated by Gamma Knife radiosurgery (GKRS) for previously embolized AVMs. METHODS: The institutional database of AVMs was retrospectively reviewed between January 2004 and March 2018. The clinical and radiological data of patients treated with GKRS for previously embolized AVMs were analyzed. Predicting factors of obliteration and hemorrhage following GKRS were assessed with univariate and multivariate regression analyses. RESULTS: The mean AVM size was significantly reduced after embolization (p < 0.001). The obliteration rate was 78.4%. Multivariate analyses showed that a lower Spetzler-Martin grade (p = 0.035) and a higher marginal dose (p = 0.007) were associated with obliteration. Post-GKRS hemorrhages occurred in 14 patients (7.4%). A longer time between diagnosis and GKRS was the only factor associated with post-GKRS hemorrhages in multivariate analysis (p = 0.022). Complications related to the combined treatment were responsible for a new permanent neurological disability in 20 patients (10.5%), and a case of death (0.5%). CONCLUSIONS: This study shows that the embolization of AVMs does not have a negative impact on the obliteration rate after radiosurgery. Embolization reduces the AVM size to a treatable volume by GKRS. However, the combined treatment results in an increased complication rate related to the addition of the risks of each treatment modality.

Validation of the French version of the ICHOM adult oral health standard set.

INTRODUCTION: The ICHOM Adult Oral Health Standard Set (AOHSS) recently developed by the ICHOM Oral Adult Health Working Group is a standard set of outcomes designed for its collection in clinical practice in dental health. The outcome standard set is made up of clinical-reported outcome measures (CROMs) and patient-reported outcome measures (PROMs). The purpose of this study was to translate and cross-culturally adapt the PROM section of the Standard Set in French for France to enable comprehensive evaluation of the patients' oral health quality of life in a French population. METHODS: The questionnaire was translated following the guidelines of the International Society for Pharmacoeconomics and Outcome Research (ISPOR). We included patients consulting in a dentistry clinic (n = 127) and seeking dental care. The PROM and CROM data were collected from all patients. Both reliability and the internal consistency were evaluated. RESULTS: The ICHOM AOHSS was successfully translated into French. We sampled and surveyed 126 patients in a dentistry clinic in France using the French translation of the ICHOM AOHSS. Cronbach's α was calculated to measure the internal consistency. The resulting Cronbach's α was 0.8, indicating acceptable homogeneity. CONCLUSIONS: The French version of the ICHOM AOHSS shows acceptable psychometric properties in terms of reliability and internal consistency. This translation is suitable for its implementation in a French-speaking patient population.

Intraoperative electron radiotherapy in early invasive ductal breast cancer: 6-year median follow-up results of a prospective monocentric registry.

BACKGROUND: Intraoperative electron radiotherapy (IOERT) can be used to treat early breast cancer during the conservative surgery thus enabling shorter overall treatment times and reduced irradiation of organs at risk. We report on our first 996 patients enrolled prospectively in a registry trial. METHODS: At Jules Bordet Institute, from February 2010 onwards, patients underwent partial IOERT of the breast. Women with unifocal invasive ductal carcinoma, aged 40 years or older, with a clinical tumour size ≤ 20 mm and tumour-free sentinel lymph node (on frozen section and immunohistochemical analysis). A 21 Gy dose was prescribed on the 90% isodose line in the tumour bed with the energy of 6 to 12 MeV (Mobetron®-IntraOp Medical). RESULTS: Thirty-seven ipsilateral tumour relapses occurred. Sixteen of those were in the same breast quadrant. Sixty patients died, and among those, 12 deaths were due to breast cancer. With 71.9 months of median follow-up, the 5-year Kaplan-Meier estimate of local recurrence was 2.7%. CONCLUSIONS: The rate of breast cancer local recurrence after IOERT is low and comparable to published results for IORT and APBI. IOERT is highly operator-dependent, and appropriate applicator sizing according to tumour size is critical. When used in a selected patient population, IOERT achieves a good balance between tumour control and late radiotherapy-mediated toxicity morbidity and mortality thanks to insignificant irradiation of organs at risk.

Leishmaniasis epidemiology in endemic areas of metropolitan France and its overseas territories from 1998 to 2020.

BACKGROUND: In France, leishmaniasis is endemic in the Mediterranean region, in French Guiana and to a lesser extent, in the French West Indies. This study wanted to provide an updated picture of leishmaniasis epidemiology in metropolitan France and in its overseas territories. METHODOLOGY/PRINCIPAL FINDINGS: Leishmaniasis cases were collected by passive notification to the French National Reference Centre for Leishmaniases (NRCL) in Montpellier from 1998 to 2020 and at the associated Centre in Cayenne (French Guiana) from 2003 to 2020. In metropolitan France, 517 autochthonous leishmaniasis cases, mostly visceral forms due to Leishmania infantum (79%), and 1725 imported cases (French Guiana excluded), mainly cutaneous leishmaniasis from Maghreb, were recorded. A slight decrease of autochthonous cases was observed during the survey period, from 0.48 cases/100,000 inhabitants per year in 1999 (highest value) to 0.1 cases/100,000 inhabitants per year in 2017 (lowest value). Conversely, imported cases increased over time (from 59.7 in the 2000s to 94.5 in the 2010s). In French Guiana, 4126 cutaneous and mucocutaneous leishmaniasis cases were reported from 2003 to 2020. The mean incidence was 103.3 cases per 100,000 inhabitants/year but varied in function of the year (from 198 in 2004 to 54 in 2006). In Guadeloupe and Martinique (French West Indies), only sporadic cases were reported. CONCLUSIONS/SIGNIFICANCE: Because of concerns about disease expansion and outbreaks in other Southern Europe countries, and leishmaniasis monitoring by the NRCL should be continued and associated with a more active surveillance.

Diagnostic accuracy and acceptability of molecular diagnosis of COVID-19 on saliva samples relative to nasopharyngeal swabs in tropical hospital and extra-hospital contexts: The COVISAL study.

A prospective study was conducted among different intra and extra-hospital populations of French Guiana to evaluate the performance of saliva testing compared to nasopharyngeal swabs. Persons aged 3 years and older with mild symptoms suggestive of COVID-19 and asymptomatic persons with a testing indication were prospectively enrolled. Nasopharyngeal and salivary samples were stored at 4°C before analysis. Both samples were analyzed with the same Real-time PCR amplification of E gene, N gene, and RdRp gene. Between July 22th and October 28th, 1159 persons were included, of which 1028 were analyzed. When only considering as positives those with 2 target genes with Ct values <35, the sensitivity of RT-PCR on saliva samples was 100% relative to nasopharyngeal samples. Specificity positive and negative predictive values were above 90%. Across a variety of cultures and socioeconomic conditions, saliva tests were generally much preferred to nasopharyngeal tests and persons seemed largely confident that they could self-sample. For positive patients defined as those with the amplification of 2 specific target genes with Ct values below 35, the sensitivity and specificity of RT-PCR on saliva samples was similar to nasopharyngeal samples despite the broad range of challenging circumstances in a tropical environment.

Spatial variations in Leishmaniasis: A biogeographic approach to mapping the distribution of Leishmania species.

Cutaneous Leishmaniasis (CL) is the most prevalent form of Leishmaniasis and is widely endemic in the Americas. Several species of Leishmania are responsible for CL, a severely neglected tropical disease and the treatment of CL vary according to the different species of Leishmania. We proposed to map the distribution of the Leishmania species reported in French Guiana (FG) using a biogeographic approach based on environmental predictors. We also measured species endemism i.e., the uniqueness of species to a defined geographic location. Our results show that the distribution patterns varied between Leishmania spp. and were spatially dependent on climatic covariates. The species distribution modelling of the eco-epidemiological spatial patterns of Leishmania spp. is the first to measure endemism based on bioclimatic factors in FG. The study also emphasizes the impact of tree cover loss and climate on the increasing distribution of L. (Viannia) braziliensis in the most anthropized regions. Detection of high-risk regions for the different between Leishmania spp. is essential for monitoring and active surveillance of the vector. As climate plays a major role in the spatial distribution of the vector and reservoir and the survival of the pathogen, climatic covariates should be included in the analysis and mapping of vector-borne diseases. This study underscores the significance of local land management and the urgency of considering the impact of climate change in the development of vector-borne disease management strategies at the global scale.

Immunoblot for the Diagnosis of Cutaneous Leishmaniasis in French Guiana.

Cutaneous leishmaniasis (CL) is firmly established in South America. We aimed to assess the detection of IgG antibodies against 14 and/or 16 kDa antigens by immunoblot (IB) for CL serological diagnosis in French Guiana, an area where many endemic pathogens could interfere with it. This study was performed retrospectively on sera from 141 patients at the Cayenne tertiary hospital: 30 were patients with confirmed CL, 71 were diagnosed with various other endemic pathogens, 11 were diagnosed with an autoimmune disease, and 29 controls had no history of CL. Antibodies bound to the 14 and/or 16 kDa antigens in 27 of the 30 CL patients' sera and in 39 of the 111 non-CL patients' sera (26 from the infectious diseases group, four from the autoimmune diseases group, and nine from the dermatology department). The method tested showed a high sensitivity (90%) and a low specificity (66%), and a diagnosis odds ratio of 17.5 (95% CI [4.6-78.0]). This IB may be helpful to exclude the diagnosis of CL, prompting physicians to look for another diagnosis in the case of a negative IB.

Monte Carlo as quality control tool of stereotactic body radiation therapy treatment plans.

PURPOSE/OBJECTIVE: The objective of this study was to verify the accuracy of treatment plans of stereotactic body radiation therapy (SBRT) and to verify the feasibility of the use of Monte Carlo (MC) as quality control (QC) on a daily basis. MATERIAL/METHODS: Using EGSnrc, a MC model of Agility™ linear accelerator was created. Various measurements (Percentage depth dose (PDD), Profiles and Output factors) were done for different fields sizes from 1x1 up to 40x40 (cm2). An iterative model optimization was performed to achieve adequate parameters of MC simulation. 40 SBRT patient's dosimetry plans were calculated by Monaco™ 3.1.1. CT images, RT-STRUCT and RT-PLAN files from Monaco™ being used as input for Moderato MC code. Finally, dose volume histogram (DVH) and paired t-tests for each contour were used for dosimetry comparison of the Monaco™ and MC. RESULTS: Validation of MC model was successful, as <2% difference comparing to measurements for all field's sizes. The main energy of electron source incident on the target was 5.8 MeV, and the full width at half maximum (FWHM) of Gaussian electron source were 0.09 and 0.2 (cm) in X and Y directions, respectively. For 40 treatment plan comparisons, the minimum absolute difference of mean dose of planning treatment planning (PTV) was 0.1% while the maximum was 6.3%. The minimum absolute difference of Max dose of PTV was 0.2% while the maximum was 8.1%. CONCLUSION: SBRT treatment plans of Monaco agreed with MC results. It possible to use MC for treatment plans verifications as independent QC tool.

Prospective Comparison of Saliva and Nasopharyngeal Swab Sampling for Mass Screening for COVID-19.

Current testing for COVID-19 relies on reverse-transcriptase polymerase chain reaction from a nasopharyngeal swab specimen. Saliva samples have advantages regarding ease and painlessness of collection, which does not require trained staff and may allow self-sampling. We enrolled 776 persons at various field-testing sites and collected nasopharyngeal and pooled saliva samples. One hundred sixty two had a positive COVID-19 RT-PCR, 61% were mildly symptomatic and 39% asymptomatic. The sensitivity of RT-PCR on saliva samples vs. nasopharygeal swabs varied depending on the patient groups considered or on Ct thresholds. There were 10 (6.2%) patients with a positive saliva sample and a negative nasopharyngeal swab, all of whom had Ct values <25 for three genes. For symptomatic patients for whom the interval between symptoms onset and sampling was <10 days sensitivity was 77% but when excluding persons with isolated N gene positivity (54/162), sensitivity was 90%. In asymptomatic patients, the sensitivity was only 24%. When we looked at patients with Cts <30, sensitivity was 83 or 88.9% when considering two genes. The relatively good performance for patients with low Cts suggests that Saliva testing could be a useful and acceptable tool to identify infectious persons in mass screening contexts, a strategically important task for contact tracing and isolation in the community.

Impact of low ionic strength on DGT sampling with standard APA gels: Effect of pH and analyte.

Only a limited and scattered knowledge is currently available on the conditions leading to the occurrence of sampling alteration at low ionic strength (<10-3 mol L-1) with DGT (diffusive gradients in thin films technique). In this study, the role of the pH and the charge of the analyte were comprehensively evaluated with DGT equipped with APA (polyacrylamide with agarose-derivative crosslinker) diffusive gels and ZrO or Chelex binding phases. The sampling of four cations (CdII, CuII, NiII and PbII) and two anions (AsV and CrVI) was compared for pH 4, 6 and 8 at common (10-2 mol L-1) and low (10-4 mol L-1) ionic strengths. Results showed that the sampling was modified at low ionic strength only in the most acidic condition (pH 4) for both anions and cations with an opposite incidence: cations' sampling was halved whereas anions' sampling was increased. Furthermore, cations sampling alteration was similarly reproduced using diffusion cell experiments, which requires only the APA gel, indicating that the binding layer does not participate in the low ionic strength effect. The intensity of DGT sampling modification was consistent with a prediction based on Donnan partitioning of analytes at gel/solution interface for several valences (from -I to + III). All these results strongly suggest that the APA diffusive gels carry positive charges that create a Donnan effect at low ionic strength. Since no ionic strength effect could be evidenced at pH 6 and 8, it can be reasonably assumed that this effect occurs only marginally for DGT deployments in most natural waters.

Cadmium Selenide Formation Influences the Production and Characteristics of Extracellular Polymeric Substances of Anaerobic Granular Sludge.

Feeding cadmium (II) and selenium (IV) simultaneously to anaerobic granular sludge with the aim of synthesizing cadmium selenide (CdSe) nanoparticles induces compositional changes in the extracellular polymeric substances (EPS) matrix of this sludge. A methanogenic anaerobic granular sludge was repeatedly exposed to Cd(II) (10-50 mg L-1) and selenite (79 mg L-1) for 300 days at pH 7.3 and 30 °C in a fed-batch feeding regime for enrichment of Se-reducing bacteria and synthesis of CdSe nanoparticles. EPS fingerprints of the granular sludge, obtained by size exclusion chromatography coupled to a fluorescence detector, showed a significant increase in the intensity of protein-like substances with > 100 kDa apparent molecular weight (aMW) upon repeated exposure to Cd(II) and Se(VI). This was accompanied by a prominent decrease in protein-like substances of aMW < 10 kDa. The fingerprint of the humic-like substances showed emergence of a new peak with aMW of 13 to 300 kDa in the EPS extracted from the Cd/Se fed granular sludge. Experiments on metal(loid)-EPS interactions showed that the CdSe nanoparticles interact mainly with loosely bound EPS (LB-EPS). This study showed that the formation of Se(0) and CdSe nanoparticles occurs in the LB-EPS fraction of the granular sludge and repeated exposure to Cd and Se induces compositional changes in the EPS matrix.

Validation of Swab Sampling and SYBR Green-Based Real-Time PCR for the Diagnosis of Cutaneous Leishmaniasis in French Guiana.

Recent studies have highlighted the interest in noninvasive sampling procedures coupled with real-time PCR methods for the detection of Leishmania species in South America. In French Guiana, the sampling method still relied on skin biopsies. Noninvasive protocols should be tested on a large annual cohort to improve routine laboratory diagnosis of cutaneous leishmaniasis. Therefore, we evaluated the performance of a new Leishmania detection and species identification protocol involving cotton swabs and SYBR green-based real-time PCR of the Hsp70 gene, coupled with Sanger sequencing. Between May 2017 and May 2018, 145 patients with ulcerated lesions compatible with cutaneous leishmaniasis were included in the study at the Cayenne Hospital and its remote health centers. Each patient underwent scrapings for a smear, skin biopsies for parasite culture and PCR-restriction fragment length polymorphism (RFLP) (RNA polymerase II), and sampling with a cotton swab for SYBR green-based PCR. The most accurate diagnostic test was the SYBR green-based PCR on swab samples, showing 98% sensitivity. The mean PCR cycle threshold (CT ) was 24.4 (minimum CT , 17; maximum CT , 36) and was <35 in 97.6% of samples. All samples positive by SYBR green-based real-time PCR were successfully identified at the species level by DNA sequencing. This new method should be considered for routine diagnosis of cutaneous leishmaniasis in South America and especially for remote areas, since noninvasive collection tools are easier to use and require fewer precautions for transportation.

Leishmania naiffi and lainsoni in French Guiana: Clinical features and phylogenetic variability.

In French Guiana, five species are associated with Cutaneous Leishmaniasis (CL). Though infections with Leishmania guyanensis, L. (V.) braziliensis and L. (L.) amazonensis have been extensively described, there are few available clinical and genetic data on L. (V.) lainsoni and L. (V.) naiffi. We determined the clinical and epidemiological features of all cases of CL due to L. (V.) naiffi and L. (V.) lainsoni diagnosed in French Guiana between 2003 and 2019. Phylogenetic analysis was performed by sequencing a portion of HSP70 and cyt b genes. Five cases of L. naiffi and 25 cases of L. lainsoni were reported. Patients infected by L. (V.) lainsoni were usually infected on gold camps, mostly along the Maroni river (60%), while L. naiffi was observed in French patients infected on the coast (100%). A high number of pediatric cases (n = 5; 20%) was observed for L. (V.) lainsoni. A mild clinical course was observed for all cases of L. (V.) naiffi. HSP70 and cyt b partial nucleotide sequence analysis revealed different geographical clusters within L. (V.) naiffi and L. (V.) lainsoni but no association were found between phylogenetic and clinical features. Our data suggest distinct socio-epidemiological features for these two Leishmania species. Patients seem to get infected with L. (V.) naiffi during leisure activities in anthropized coastal areas, while L. (V.) lainsoni shares common features with L. (V.) guyanensis and braziliensis and seems to be acquired during professional activities in primary forest regions. Phylogenetic analysis has provided information on the intraspecific genetic variability of L. (V.) naiffi and L. (V.) lainsoni and how these genotypes are distributed at the geographic level.

Retreatment of Root Canals Filled with BioRoot RCS: An In Vitro Experimental Study.

INTRODUCTION: The purpose of this study was to compare the speed of removal of root canal filling material and re-establishment of apical patency in root canals filled with a tricalcium silicate-based sealer (BioRoot RCS [BRCS]; Septodont, Saint-Maur-des-Fossés, France) versus a zinc oxide-eugenol sealer (Pulp Canal Sealer [PCS]; Sybron Endo Kerr, Orange, CA) and to analyze the effect of the operator's experience. METHODS: One hundred twenty root canals of 40 Dentalike dental simulators (Dentsply Sirona, York, PA) were shaped with a WaveOne (Dentsply Sirona) reciprocating file using short 3-mm strokes. Root canals were obturated using a single gutta-percha cone and either BRCS or PCS. Samples treated either with BRCS or PCS were equally dispatched between experienced practitioners and junior practitioners. The time required to remove root filling material and establish apical patency was recorded for each root canal. Samples were compared according to the sealer used and the practitioner's experience (Mann-Whitney test). RESULTS: One hundred fifteen root canals were successfully retreated. No differences in the time required to remove the filling material were observed between the 2 materials for mesiobuccal or distobuccal canals (P > .05). In contrast, the procedure was longer for palatal canals filled with BRCS compared with PCS (79.10 vs 182.45 seconds, P < .01). Experienced practitioners took significantly less time than junior practitioners (P < .05). CONCLUSIONS: BRCS can be successfully removed from root canals as quickly as a zinc oxide-eugenol sealer in both mesiobuccal and distobuccal canals but not in palatal ones. The duration of the procedure was affected by the operator's experience independent of the filling material used or the canal type.

American cutaneous leishmaniasis in French Guiana: an epidemiological update and study of environmental risk factors.

BACKGROUND: American cutaneous leishmaniasis (ACL) is endemic in French Guiana. Its epidemiology is evolving, notably because of immigration, anthropization of natural areas, and new microbiological methods. Our first objective was to update epidemiological data. Our second objective was to look for risk factors of ACL. METHODS: This multicentric study was conducted from October 2017 to June 2018 in French Guiana. Patients with suspicion of mucocutaneous leishmaniasis were included in case of positive smear, culture, or PCR-RFLP on skin biopsy. RESULTS: One hundred and twenty-three patients met the inclusion criteria. Among those patients, 59.3% were Brazilian, mostly gold miners. Most of them (58%) were between 16 and 40 years old, and 69% were male. A large proportion of patients lived in traditional wooden houses (51%). Patients living in coastal towns were usually infected during trips to the primary forest (60%) and had a shorter time to diagnosis than workers of the hinterland. Among environmental risk factors, the presence of a water spring (40%) and dogs around houses (40%) were frequently reported. Leishmania guyanensis represented 80% of cases, followed by Leishmania braziliensis (6%), Leishmania naiffi (2%), and Leishmania amazonensis (1%). CONCLUSIONS: Gold mining and trips to the primary forest represent high-risk situations for ACL in French Guiana, where the population of infected patients is dominated by Brazilian immigrants. Possible environmental risk factors such as the presence of dogs, water sources, and traditional wooden houses require further investigation.