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2.
Cancer ; 130(9): 1577-1589, 2024 May 01.
Article de Anglais | MEDLINE | ID: mdl-38288941

RÉSUMÉ

Management of venous thromboembolism (VTE) in patients with primary and metastatic brain tumors (BT) is challenging because of the risk of intracranial hemorrhage (ICH). There are no prospective clinical trials evaluating safety and efficacy of direct oral anticoagulants (DOACs), specifically in patients with BT, but they are widely used for VTE in this population. A group of neuro-oncology experts convened to provide practical clinical guidance for the off-label use of DOACs in treating VTE in patients with BT. We searched PubMed for the following terms: BTs, glioma, glioblastoma (GBM), brain metastasis, VTE, heparin, low-molecular-weight heparin (LWMH), DOACs, and ICH. Although prospective clinical trials are needed, the recommendations presented aim to assist clinicians in making informed decisions regarding DOACs for VTE in patients with BT.


Sujet(s)
Tumeurs du cerveau , Tumeurs , Thromboembolisme veineux , Humains , Anticoagulants/effets indésirables , Thromboembolisme veineux/épidémiologie , Hémorragie , Études prospectives , Tumeurs/traitement médicamenteux , Récidive tumorale locale/traitement médicamenteux , Tumeurs du cerveau/complications , Tumeurs du cerveau/traitement médicamenteux , Administration par voie orale
3.
Magn Reson Med ; 91(6): 2559-2567, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38205934

RÉSUMÉ

PURPOSE: To investigate the safety and value of hyperpolarized (HP) MRI of [1-13C]pyruvate in healthy volunteers using deuterium oxide (D2O) as a solvent. METHODS: Healthy volunteers (n = 5), were injected with HP [1-13C]pyruvate dissolved in D2O and imaged with a metabolite-specific 3D dual-echo dynamic EPI sequence at 3T at one site (Site 1). Volunteers were monitored following the procedure to assess safety. Image characteristics, including SNR, were compared to data acquired in a separate cohort using water as a solvent (n = 5) at another site (Site 2). The apparent spin-lattice relaxation time (T1) of [1-13C]pyruvate was determined both in vitro and in vivo from a mono-exponential fit to the image intensity at each time point of our dynamic data. RESULTS: All volunteers completed the study safely and reported no adverse effects. The use of D2O increased the T1 of [1-13C]pyruvate from 66.5 ± 1.6 s to 92.1 ± 5.1 s in vitro, which resulted in an increase in signal by a factor of 1.46 ± 0.03 at the time of injection (90 s after dissolution). The use of D2O also increased the apparent relaxation time of [1-13C]pyruvate by a factor of 1.4 ± 0.2 in vivo. After adjusting for inter-site SNR differences, the use of D2O was shown to increase image SNR by a factor of 2.6 ± 0.2 in humans. CONCLUSIONS: HP [1-13C]pyruvate in D2O is safe for human imaging and provides an increase in T1 and SNR that may improve image quality.


Sujet(s)
Imagerie par résonance magnétique , Acide pyruvique , Humains , Études de faisabilité , Imagerie par résonance magnétique/méthodes , Encéphale/imagerie diagnostique , Isotopes du carbone , Solvants
4.
Lancet Infect Dis ; 23(9): 1062-1071, 2023 09.
Article de Anglais | MEDLINE | ID: mdl-37178706

RÉSUMÉ

BACKGROUND: Novel oral poliovirus vaccine type 2 (nOPV2) was developed by modifying the Sabin strain to increase genetic stability and reduce risk of seeding new circulating vaccine-derived poliovirus type 2 outbreaks. Bivalent oral poliovirus vaccine (bOPV; containing Sabin types 1 and 3) is the vaccine of choice for type 1 and type 3 outbreak responses. We aimed to assess immunological interference between nOPV2 and bOPV when administered concomitantly. METHODS: We conducted an open-label, non-inferiority, randomised, controlled trial at two clinical trial sites in Dhaka, Bangladesh. Healthy infants aged 6 weeks were randomly assigned (1:1:1) using block randomisation, stratified by site, to receive nOPV2 only, nOPV2 plus bOPV, or bOPV only, at the ages of 6 weeks, 10 weeks, and 14 weeks. Eligibility criteria included singleton and full term (≥37 weeks' gestation) birth and parents intending to remain in the study area for the duration of study follow-up activities. Poliovirus neutralising antibody titres were measured at the ages of 6 weeks, 10 weeks, 14 weeks, and 18 weeks. The primary outcome was cumulative immune response for all three poliovirus types at the age of 14 weeks (after two doses) and was assessed in the modified intention-to-treat population, which was restricted to participants with adequate blood specimens from all study visits. Safety was assessed in all participants who received at least one dose of study product. A non-inferiority margin of 10% was used to compare single and concomitant administration. This trial is registered with ClinicalTrials.gov, NCT04579510. FINDINGS: Between Feb 8 and Sept 26, 2021, 736 participants (244 in the nOPV2 only group, 246 in the nOPV2 plus bOPV group, and 246 in the bOPV only group) were enrolled and included in the modified intention-to-treat analysis. After two doses, 209 (86%; 95% CI 81-90) participants in the nOPV2 only group and 159 (65%; 58-70) participants in the nOPV2 plus bOPV group had a type 2 poliovirus immune response; 227 (92%; 88-95) participants in the nOPV2 plus bOPV group and 229 (93%; 89-96) participants in the bOPV only group had a type 1 response; and 216 (88%; 83-91) participants in the nOPV2 plus bOPV group and 212 (86%; 81-90) participants in the bOPV only group had a type 3 response. Co-administration was non-inferior to single administration for types 1 and 3, but not for type 2. There were 15 serious adverse events (including three deaths, one in each group, all attributable to sudden infant death syndrome); none were attributed to vaccination. INTERPRETATION: Co-administration of nOPV2 and bOPV interfered with immunogenicity for poliovirus type 2, but not for types 1 and 3. The blunted nOPV2 immunogenicity we observed would be a major drawback of using co-administration as a vaccination strategy. FUNDING: The US Centers for Disease Control and Prevention.


Sujet(s)
Poliomyélite , Poliovirus , Nourrisson , Humains , Vaccin antipoliomyélitique oral , Poliomyélite/épidémiologie , Vaccin antipoliomyélitique inactivé , Bangladesh/épidémiologie , Calendrier vaccinal , Immunogénicité des vaccins , Anticorps antiviraux
5.
Cancer ; 129(19): 3010-3022, 2023 10 01.
Article de Anglais | MEDLINE | ID: mdl-37246417

RÉSUMÉ

BACKGROUND: Glioblastoma (GBM) is the most common malignant primary brain tumor. Emerging reports have suggested that racial and socioeconomic disparities influence the outcomes of patients with GBM. No studies to date have investigated these disparities controlling for isocitrate dehydrogenase (IDH) mutation and O-6-methylguanine-DNA methyltransferase (MGMT) status. METHODS: Adult patients with GBM were retrospectively reviewed at a single institution from 2008 to 2019. Univariable and multivariable complete survival analyses were performed. A Cox proportional hazards model was used to assess the effect of race and socioeconomic status controlling for a priori selected variables with known relevance to survival. RESULTS: In total, 995 patients met inclusion criteria. Of these, 117 patients (11.7%) were African American (AA). The median overall survival for the entire cohort was 14.23 months. In the multivariable model, AA patients had better survival compared with White patients (hazard ratio [HR], 0.37; 95% confidence interval [CI], 0.2-0.69). The observed survival difference was significant in both a complete case analysis model and a multiple imputations model accounting for missing molecular data and controlling for treatment and socioeconomic status. AA patients with low income (HR, 2.17; 95% CI, 1.04-4.50), public insurance (HR, 2.25; 95% CI, 1.04-4.87), or no insurance (HR, 15.63; 95% CI, 2.72-89.67) had worse survival compared with White patients with low income, public insurance, or no insurance, respectively. CONCLUSIONS: Significant racial and socioeconomic disparities were identified after controlling for treatment, GBM genetic profile, and other variables associated with survival. Overall, AA patients demonstrated better survival. These findings may suggest the possibility of a protective genetic advantage in AA patients. PLAIN LANGUAGE SUMMARY: To best personalize treatment for and understand the causes of glioblastoma, racial and socioeconomic influences must be examined. The authors report their experience at the O'Neal Comprehensive Cancer Center in the deep south. In this report, contemporary molecular diagnostic data are included. The authors conclude that there are significant racial and socioeconomic disparities that influence glioblastoma outcome and that African American patients do better.


Sujet(s)
Tumeurs du cerveau , Glioblastome , Adulte , Humains , Glioblastome/génétique , Glioblastome/thérapie , Glioblastome/diagnostic , Études rétrospectives , , Tumeurs du cerveau/génétique , Tumeurs du cerveau/thérapie , Tumeurs du cerveau/diagnostic , Analyse de survie , Disparités d'accès aux soins
6.
J Infect Dis ; 226(5): 852-861, 2022 09 13.
Article de Anglais | MEDLINE | ID: mdl-34610135

RÉSUMÉ

BACKGROUND: Primary intestinal immunity through viral replication of live oral vaccine is key to interrupt poliovirus transmission. We assessed viral fecal shedding from infants administered Sabin monovalent poliovirus type 2 vaccine (mOPV2) or low and high doses of 2 novel OPV2 (nOPV2) vaccine candidates. METHODS: In 2 randomized clinical trials in Panama, a control mOPV2 study (October 2015 to April 2016) and nOPV2 study (September 2018 to October 2019), 18-week-old infants vaccinated with bivalent oral poliovirus vaccine/inactivated poliovirus vaccine received 1 or 2 study vaccinations 28 days apart. Stools were assessed for poliovirus RNA by polymerase chain reaction (PCR) and live virus by culture for 28 days postvaccination. RESULTS: Shedding data were available from 621 initially reverse-transcription PCR-negative infants (91 mOPV2, 265 nOPV2-c1, 265 nOPV2-c2 recipients). Seven days after dose 1, 64.3% of mOPV2 recipients and 31.3%-48.5% of nOPV2 recipients across groups shed infectious type 2 virus. Respective rates 7 days after dose 2 decreased to 33.3% and 12.9%-22.7%, showing induction of intestinal immunity. Shedding of both nOPV2 candidates ceased at similar or faster rates than mOPV2. CONCLUSIONS: Viral shedding of either nOPV candidate was similar or decreased relative to mOPV2, and all vaccines showed indications that the vaccine virus was replicating sufficiently to induce primary intestinal mucosal immunity.


Sujet(s)
Poliomyélite , Poliovirus , Anticorps antiviraux , Humains , Nourrisson , Vaccin antipoliomyélitique inactivé , Vaccin antipoliomyélitique oral , Essais contrôlés randomisés comme sujet , Vaccins atténués
8.
Cancers (Basel) ; 12(1)2020 Jan 01.
Article de Anglais | MEDLINE | ID: mdl-31906320

RÉSUMÉ

Neurofibromatosis type 1 (NF1) is an autosomal dominant tumor predisposition syndrome that affects children and adults. Individuals with NF1 are at high risk for central nervous system neoplasms including gliomas. The purpose of this review is to discuss the spectrum of intracranial gliomas arising in individuals with NF1 with a focus on recent preclinical and clinical data. In this review, possible mechanisms of gliomagenesis are discussed, including the contribution of different signaling pathways and tumor microenvironment. Furthermore, we discuss the recent notable advances in the developing therapeutic landscape for NF1-associated gliomas including clinical trials and collaborative efforts.

9.
PLoS Med ; 16(5): e1002810, 2019 05.
Article de Anglais | MEDLINE | ID: mdl-31136584

RÉSUMÉ

BACKGROUND: Low-grade gliomas cause significant neurological morbidity by brain invasion. There is no universally accepted objective technique available for detection of enlargement of low-grade gliomas in the clinical setting; subjective evaluation by clinicians using visual comparison of longitudinal radiological studies is the gold standard. The aim of this study is to determine whether a computer-assisted diagnosis (CAD) method helps physicians detect earlier growth of low-grade gliomas. METHODS AND FINDINGS: We reviewed 165 patients diagnosed with grade 2 gliomas, seen at the University of Alabama at Birmingham clinics from 1 July 2017 to 14 May 2018. MRI scans were collected during the spring and summer of 2018. Fifty-six gliomas met the inclusion criteria, including 19 oligodendrogliomas, 26 astrocytomas, and 11 mixed gliomas in 30 males and 26 females with a mean age of 48 years and a range of follow-up of 150.2 months (difference between highest and lowest values). None received radiation therapy. We also studied 7 patients with an imaging abnormality without pathological diagnosis, who were clinically stable at the time of retrospective review (14 May 2018). This study compared growth detection by 7 physicians aided by the CAD method with retrospective clinical reports. The tumors of 63 patients (56 + 7) in 627 MRI scans were digitized, including 34 grade 2 gliomas with radiological progression and 22 radiologically stable grade 2 gliomas. The CAD method consisted of tumor segmentation, computing volumes, and pointing to growth by the online abrupt change-of-point method, which considers only past measurements. Independent scientists have evaluated the segmentation method. In 29 of the 34 patients with progression, the median time to growth detection was only 14 months for CAD compared to 44 months for current standard of care radiological evaluation (p < 0.001). Using CAD, accurate detection of tumor enlargement was possible with a median of only 57% change in the tumor volume as compared to a median of 174% change of volume necessary to diagnose tumor growth using standard of care clinical methods (p < 0.001). In the radiologically stable group, CAD facilitated growth detection in 13 out of 22 patients. CAD did not detect growth in the imaging abnormality group. The main limitation of this study was its retrospective design; nevertheless, the results depict the current state of a gold standard in clinical practice that allowed a significant increase in tumor volumes from baseline before detection. Such large increases in tumor volume would not be permitted in a prospective design. The number of glioma patients (n = 56) is a limitation; however, it is equivalent to the number of patients in phase II clinical trials. CONCLUSIONS: The current practice of visual comparison of longitudinal MRI scans is associated with significant delays in detecting growth of low-grade gliomas. Our findings support the idea that physicians aided by CAD detect growth at significantly smaller volumes than physicians using visual comparison alone. This study does not answer the questions whether to treat or not and which treatment modality is optimal. Nonetheless, early growth detection sets the stage for future clinical studies that address these questions and whether early therapeutic interventions prolong survival and improve quality of life.


Sujet(s)
Tumeurs du cerveau/imagerie diagnostique , Prolifération cellulaire , Gliome/imagerie diagnostique , Imagerie par résonance magnétique , Tumeurs du cerveau/anatomopathologie , Femelle , Gliome/anatomopathologie , Humains , Études longitudinales , Mâle , Adulte d'âge moyen , Grading des tumeurs , Invasion tumorale , Valeur prédictive des tests , Études rétrospectives , Facteurs temps , Charge tumorale
10.
J Biol Chem ; 286(11): 9031-7, 2011 Mar 18.
Article de Anglais | MEDLINE | ID: mdl-21296890

RÉSUMÉ

DNA methylation is a major epigenetic modification that regulates gene expression. Dnmt1, the maintenance DNA methylation enzyme, is abundantly expressed in the adult brain and is mainly located in the nuclear compartment, where it has access to chromatin. Hypomethylation of CpG islands at intron 1 of the SNCA gene has recently been reported to result in overexpression of α-synuclein in Parkinson disease (PD) and related disorders. We therefore investigated the mechanisms underlying altered DNA methylation in PD and dementia with Lewy bodies (DLB). We present evidence of reduction of nuclear Dnmt1 levels in human postmortem brain samples from PD and DLB patients as well as in the brains of α-synuclein transgenic mice models. Furthermore, sequestration of Dnmt1 in the cytoplasm results in global DNA hypomethylation in human and mouse brains, involving CpG islands upstream of SNCA, SEPW1, and PRKAR2A genes. We report that association of Dnmt1 and α-synuclein might mediate aberrant subcellular localization of Dnmt1. Nuclear Dnmt1 levels were partially rescued by overexpression of Dnmt1 in neuronal cell cultures and in α-synuclein transgenic mice brains. Our results underscore a novel mechanism for epigenetic dysregulation in Lewy body diseases, which might underlie the decrease in DNA methylation reported for PD and DLB.


Sujet(s)
Encéphale/métabolisme , DNA (cytosine-5-)-methyltransferase/métabolisme , Méthylation de l'ADN , Épigenèse génétique , Maladie à corps de Lewy/métabolisme , alpha-Synucléine/métabolisme , Adulte , Animaux , Ilots CpG , Cyclic AMP-Dependent Protein Kinase RIIalpha Subunit/génétique , Cyclic AMP-Dependent Protein Kinase RIIalpha Subunit/métabolisme , DNA (Cytosine-5-)-methyltransferase 1 , DNA (cytosine-5-)-methyltransferase/génétique , Humains , Maladie à corps de Lewy/génétique , Souris , Souris knockout , Sélénoprotéine W/génétique , Sélénoprotéine W/métabolisme , alpha-Synucléine/génétique
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