Biological efficacy of simulated radiolabeled Lipiodol® ultra-fluid and microspheres for various beta emitters: study based on VX2 tumors.

Background: Radioembolization is one therapeutic option for the treatment of locally early-stage hepatocellular carcinoma. The aim of this study was to evaluate the distribution of Lipiodol® ultra-fluid and microspheres and to simulate their effectiveness with different beta emitters (Y, Re, P, Ho, I, and Lu) on VX2 tumors implanted in the liver of 30 New Zealand rabbits.

Results: Twenty-three out of 30 rabbits had exploitable data: 14 in the group that received Lipiodol® ultra-fluid (group L), 6 in the group that received microspheres (group M), and 3 in the control group (group C).

Performance study of a 360° CZT camera for monitoring Lu-PSMA treatment.

Background: The aim of this study was to investigate the quantification performance of a 360° CZT camera for Lu-based treatment monitoring.

Methods: Three phantoms with known Lu activity concentrations were acquired: (1) a uniform cylindrical phantom for calibration, (2) a NEMA IEC body phantom for analysis of different-sized spheres to optimise quantification parameters and (3) a phantom containing two large vials simulating organs at risk for tests. Four sets of reconstruction parameters were tested: (1) Scatter, (2) Scatter and Point Spread Function Recovery (PSFR), (3) PSFR only and (4) Penalised likelihood option and Scatter, varying the number of updates (iterations × subsets) with CT-based attenuation correction only.

Concepts and methods for the dosimetry of radioembolisation of the liver with Y-90-loaded microspheres.

This article aims at presenting in a didactic way, dosimetry concepts and methods that are relevant for radio-embolization of the liver with Y-microspheres. The application of the medical internal radiation dose formalism to radio-embolization is introduced. This formalism enables a simplified dosimetry, where the absorbed dose in a given tissue depends on only its mass and initial activity.

Zaire ebolavirus surveillance near the Bikoro region of the Democratic Republic of the Congo during the 2018 outbreak reveals presence of seropositive bats.

On the 8th of May, 2018, an outbreak of Ebola virus disease (EVD) was declared, originating in the Bikoro region of the Democratic Republic of the Congo (DRC) near the border with neighboring Republic of the Congo (ROC). Frequent trade and migration occur between DRC and ROC-based communities residing along the Congo River. In June 2018, a field team was deployed to determine whether Zaire ebolavirus (Ebola virus (EBOV)) was contemporaneously circulating in local bats at the human-animal interface in ROC near the Bikoro EVD outbreak.

International recommendations for personalised selective internal radiation therapy of primary and metastatic liver diseases with yttrium-90 resin microspheres.

Purpose: A multidisciplinary expert panel convened to formulate state-of-the-art recommendations for optimisation of selective internal radiation therapy (SIRT) with yttrium-90 (Y)-resin microspheres.

Methods: A steering committee of 23 international experts representing all participating specialties formulated recommendations for SIRT with Y-resin microspheres activity prescription and post-treatment dosimetry, based on literature searches and the responses to a 61-question survey that was completed by 43 leading experts (including the steering committee members). The survey was validated by the steering committee and completed anonymously.

Prognostic impact of bone metastases detected by F-DOPA PET in patients with metastatic midgut neuroendocrine tumors.

Objectives: Bone metastases (BM) may influence negatively the prognosis of midgut neuroendocrine tumors (NET). The diagnostic sensitivity of F-DOPA PET for midgut NET and associated metastases is high. This study aimed to assess the prognostic impact of BM detected by F-DOPA PET in metastatic midgut NET.

Relationship of Tumor Radiation-absorbed Dose to Survival and Response in Hepatocellular Carcinoma Treated with Transarterial Radioembolization with Y in the SARAH Study.

Background Little is known about factors that influence the efficacy of transarterial radioembolization (TARE). Purpose To determine the relationship between tumor radiation-absorbed dose and survival and tumor response in locally advanced inoperable hepatocellular carcinoma treated with TARE. Materials and Methods This was a secondary analysis of prospectively acquired data (between December 2011 and March 2015) from participants who received TARE in the Sorafenib versus Radioembolization in Advanced Hepatocellular Carcinoma (SARAH) trial (ClinicalTrials.

Regulation of alginate catabolism involves a GntR family repressor in the marine flavobacterium Zobellia galactanivorans DsijT.

Marine flavobacteria possess dedicated Polysaccharide Utilization Loci (PULs) enabling efficient degradation of a variety of algal polysaccharides. The expression of these PULs is tightly controlled by the presence of the substrate, yet details on the regulatory mechanisms are still lacking. The marine flavobacterium Zobellia galactanivorans DsijT digests many algal polysaccharides, including alginate from brown algae.

A Sensitive Magnetic Arsenite-Specific Biosensor Hosted in Magnetotactic Bacteria.

According to the World Health Organization, arsenic is the water contaminant that affects the largest number of people worldwide. To limit its impact on the population, inexpensive, quick, and easy-to-use systems of detection are required. One promising solution could be the use of whole-cell biosensors, which have been extensively studied and could meet all these criteria even though they often lack sensitivity.

Magnetosomes: biogenic iron nanoparticles produced by environmental bacteria.

The scientific community's interest in magnetotactic bacteria has increased substantially in recent decades. These prokaryotes have the particularity of synthesizing nanomagnets, called magnetosomes. The majority of research is based on several scientific questions.

Tamoxifen Metabolism and Efficacy in Breast Cancer: A Prospective Multicenter Trial.

Levels of endoxifen, the most active metabolite of tamoxifen, vary by the highly polymorphic cytochrome P450 (CYP) 2D6 enzyme. We prospectively investigated tamoxifen efficacy by serum endoxifen levels and the tamoxifen activity score (TAS). A prospective observational multicenter study included postmenopausal women with an estrogen receptor-positive breast cancer receiving first-line tamoxifen, 20 mg daily in the neoadjuvant or metastatic setting, recruited between February 2009 and May 2014.

A gate evaluation of the sources of error in quantitative Y PET.

Purpose: Accurate reconstruction of the dose delivered by Y microspheres using a postembolization PET scan would permit the establishment of more accurate dose-response relationships for treatment of hepatocellular carcinoma with Y. However, the quality of the PET data obtained is compromised by several factors, including poor count statistics and a very high random fraction. This work uses Monte Carlo simulations to investigate what impact factors other than low count statistics have on the quantification of Y PET.

A gate evaluation of the sources of error in quantitative Y PET.

Purpose: Accurate reconstruction of the dose delivered by Y microspheres using a postembolization PET scan would permit the establishment of more accurate dose-response relationships for treatment of hepatocellular carcinoma with Y. However, the quality of the PET data obtained is compromised by several factors, including poor count statistics and a very high random fraction. This work uses Monte Carlo simulations to investigate what impact factors other than low count statistics have on the quantification of Y PET.

Antiretroviral Drug Resistance Among Children and Youth in the United States With Perinatal HIV.

Among 234 US youths with perinatal human immunodeficiency virus, 75% had antiretroviral resistance, substantially higher than that of the reference laboratory overall (36%-44%). Resistance to newer antiretrovirals and to all antiretrovirals in a class was uncommon. The only factor independently associated with future resistance was a higher peak viral load.

Implementation and validation of collapsed cone superposition for radiopharmaceutical dosimetry of photon emitters.

Two collapsed cone (CC) superposition algorithms have been implemented for radiopharmaceutical dosimetry of photon emitters. The straight CC (SCC) superposition method uses a water energy deposition kernel (EDKw) for each electron, positron and photon components, while the primary and scatter CC (PSCC) superposition method uses different EDKw for primary and once-scattered photons. PSCC was implemented only for photons originating from the nucleus, precluding its application to positron emitters.

Prevalence and Persistence of Varicella Antibodies in Previously Immunized Children and Youth With Perinatal HIV-1 Infection.

Background: Two doses of live-attenuated varicella-zoster vaccine are recommended for human immunodeficiency virus 1 (HIV-1)-infected children with CD4% ≥ 15%. We determined the prevalence and persistence of antibody in immunized children with perinatal HIV (PHIV) and their association with number of vaccinations, combination antiretroviral therapy (cART), and HIV status.

Methods: The Adolescent Master Protocol is an observational study of children with PHIV and perinatally HIV-exposed but uninfected (PHEU) children conducted at 15 US sites.

CYP2D6 genotype- and endoxifen-guided tamoxifen dose escalation increases endoxifen serum concentrations without increasing side effects.

Breast cancer patients with absent or reduced CYP2D6 activity and consequently low endoxifen levels may benefit less from tamoxifen treatment. CYP2D6 poor and intermediate metabolizers may need a personalized increased tamoxifen dose to achieve effective endoxifen serum concentrations, without increasing toxicity. From a prospective study population of early breast cancer patients using tamoxifen (CYPTAM: NTR1509), 12 CYP2D6 poor and 12 intermediate metabolizers were selected and included in a one-step tamoxifen dose escalation study during 2 months.

Clinical and genetic risk factors for epirubicin-induced cardiac toxicity in early breast cancer patients.

Anthracycline-induced cardiotoxicity (ACT) is a well-known serious adverse drug reaction leading to substantial morbidity. The purpose of this study was to assess ACT occurrence and clinical and genetic risk factors in early breast cancer patients. In 6 genes of interest (ABCC1, ABCC2, CYBA, NCF4, RAC2, SLC28A3), 10 single nucleotide polymorphisms (SNPs) involved in ACT were selected based on a literature search.

Medical physics personnel for medical imaging: requirements, conditions of involvement and staffing levels-French recommendations.

The French regulations concerning the involvement of medical physicists in medical imaging procedures are relatively vague. In May 2013, the ASN and the SFPM issued recommendations regarding Medical Physics Personnel for Medical Imaging: Requirements, Conditions of Involvement and Staffing Levels. In these recommendations, the various areas of activity of medical physicists in radiology and nuclear medicine have been identified and described, and the time required to perform each task has been evaluated.

Impact of genetic variability and treatment-related factors on outcome in early breast cancer patients receiving (neo-) adjuvant chemotherapy with 5-fluorouracil, epirubicin and cyclophosphamide, and docetaxel.

To assess the impact of patient-related factors, including genetic variability in genes involved in the metabolism of chemotherapeutic agents, on breast cancer-specific survival (BCSS) and recurrence-free interval (RFI). We selected early breast cancer patients treated between 2000 and 2010 with 4-6 cycles of (neo-)adjuvant 5-fluorouracil, epirubicin, and cyclophosphamide (FEC) or 3 cycles FEC followed by 3 cycles docetaxel. Tumor stage/subtype; febrile neutropenia and patient-related factors such as selected single nucleotide polymorphisms and baseline laboratory parameters were evaluated.

A new approach for dose calculation in targeted radionuclide therapy (TRT) based on collapsed cone superposition: validation with (90)Y.

To speed-up the absorbed dose (AD) computation while accounting for tissue heterogeneities, a Collapsed Cone (CC) superposition algorithm was developed and validated for (90)Y. The superposition was implemented with an Energy Deposition Kernel scaled with the radiological distance, along with CC acceleration. The validation relative to Monte Carlo simulations was performed on 6 phantoms involving soft tissue, lung and bone, a radioembolisation treatment and a simulated bone metastasis treatment.