Back to Authors

Port, John D.

https://orcid.org/0000-0002-4237-7776

Mayo Clinic

Mayo Clinic

Citations 54

Editorial for “Characterization of Brain Abnormalities in a Lactational Neurodevelopmental Poly I:C Rat Model of Schizophrenia and Depression Using Machine‐Learning and Quantitative MRI”
Port, John D. , Port, John D

Journal of Magnetic Resonance Imaging | November 12, 2024 | Volume: 61 | Issue: 5 | Pages: 2292-2293

10.1002/jmri.29644 Get It

Sleep Apnea and the Glymphatic System: Support for the Importance of Brainwashing
Port, John D. , Port, John D

Radiology | June 18, 2024 | Volume: 311 | Issue: 3 | Pages: No page available

10.1148/radiol.241440 Get It

The effect of intrathecal recombinant arylsulfatase A therapy on structural brain magnetic resonance imaging in children with metachromatic leukodystrophy
Groeschel, Samuel , Beerepoot, Shanice , Amedick, Lucas Bastian, Krägeloh‐Mann, I., Li, Jing , Whiteman, David , Port, John D. , Whiteman, David A H , Port, John D , Beerepoot, Shanice , Wolf, Nicole I

Journal of Inherited Metabolic Disease | February 7, 2024 | Volume: 47 | Issue: 4 | Pages: 778-791

10.1002/jimd.12706 Get It

Abstract This study aimed to evaluate the effect of intrathecal (IT) recombinant human arylsulfatase A (rhASA) on magnetic resonance imaging (MRI)‐assessed brain tissue changes in children with metachromatic leukodystrophy (MLD). In total, 510 MRI scans were collected from 12 intravenous (IV) rhASA‐treated children with MLD, 24 IT rhASA‐treated children with MLD, 32 children with untreated MLD, and 156 normally developing children. Linear mixed models were fitted to analyze the time courses of gray matter (GM) volume and fractional anisotropy (FA) in the posterior limb of the internal capsule. Time courses for demyelination load and FA in the centrum semiovale were visualized using locally estimated scatterplot smoothing regression curves. All assessed imaging parameters demonstrated structural evidence of neurological deterioration in children with MLD. GM volume was significantly lower at follow‐up (median duration, 104 weeks) in IV rhASA‐treated versus IT rhASA‐treated children. GM volume decline over time was steeper in children receiving low‐dose (10 or 30 mg) versus high‐dose (100 mg) IT rhASA. Similar effects were observed for demyelination. FA in the posterior limb of the internal capsule showed a higher trend over time in IT rhASA‐treated versus children with untreated MLD, but FA parameters were not different between children receiving the low doses versus those receiving the high dose. GM volume in IT rhASA‐treated children showed a strong positive correlation with 88‐item Gross Motor Function Measure score over time. In some children with MLD, IT administration of high‐dose rhASA may delay neurological deterioration (assessed using MRI), offering potential therapeutic benefit.
Editorial for “Preoperative Subtyping ofWHOGrade 1 Meningiomas Using a Single‐Shot UltrafastMR T2Mapping”
Agarwal, Nivedita , Port, John D.

Journal of Magnetic Resonance Imaging | December 23, 2023 | Volume: 60 | Issue: 3 | Pages: 977-978

10.1002/jmri.29191 Get It

MRI Reveals Connectivity of Cortical Lesions to White Matter Lesions in Multiple Sclerosis. (P6.107)
Tillema, Jan‐Mendelt , Weigand, Stephen D. , Mandrekar, Jayawant, Shu, Yunhong , Lucchinetti, Claudia F. , Pirko, Istvan, Port, John D.

Neurology | December 6, 2023 | Volume: 84 | Issue: 14_supplement | Pages: No page available

10.1212/wnl.84.14_supplement.p6.107 Get It

Neurohormonal response patterns to hunger, satiation, and postprandial fullness in normal weight, anorexia nervosa, and obesity
Campos, Alejandro , Marek, Tomáš , Ghusn, Wissam , Cifuentes, Lizeth , Sim, Leslie , Camilleri, Michael , Dayyeh, Barham Abu, Acosta, Andrés , Calderon, Gerardo, Camilleri, M , Acosta, Andres , Ghusn, Wissam , Campos, Alejandro , Calderon-Lopez, Gerardo , Port, John D.

Neurogastroenterology & Motility | November 6, 2023 | Volume: 36 | Issue: 1 | Pages: No page available

10.1111/nmo.14695 Get It

AbstractBackgroundFood intake is regulated by homeostatic and hedonic systems that interact in a complex neuro‐hormonal network. Dysregulation in energy intake can lead to obesity (OB) or anorexia nervosa (AN). However, little is known about the neurohormonal response patterns to food intake in normal weight (NW), OB, and AN.Material & MethodsDuring an ad libitum nutrient drink (Ensure®) test (NDT), participants underwent three pseudo‐continuous arterial spin labeling (pCASL) MRI scans. The first scan was performed before starting the NDT after a > 12 h overnight fast (Hunger), the second after reaching maximal fullness (Satiation), and the third 30‐min after satiation (postprandial fullness). We measured blood levels of ghrelin, cholecystokinin (CCK), glucagon‐like peptide (GLP‐1), and peptide YY (PYY) with every pCASL‐MRI scan. Semiquantitative cerebral blood flow (CBF) maps in mL/100 gr brain/min were calculated and normalized (nCBF) with the CBF in the frontoparietal white matter. The hypothalamus (HT), nucleus accumbens [NAc] and dorsal striatum [DS] were selected as regions of interest (ROIs).ResultsA total of 53 participants, 7 with AN, 17 with NW (body‐mass index [BMI] 18.5–24.9 kg/m2), and 29 with OB (BMI ≥30 kg/m2) completed the study. The NW group had a progressive decrease in all five ROIs during the three stages of food intake (hunger, satiation, and post‐prandial fullness). In contrast, participants with OB showed a minimal change from hunger to postprandial fullness in all five ROIs. The AN group had a sustained nCBF in the HT and DS, from hunger to satiation, with a subsequent decrease in nCBF from satiation to postprandial fullness. All three groups had similar hormonal response patterns with a decrease in ghrelin, an increase in GLP‐1 and PYY, and no change in CCK.ConclusionConditions of regulated (NW) and dysregulated (OB and AN) energy intake are associated with distinctive neurohormonal activity patterns in response to hunger, satiation, and postprandial fullness.
Optimizing TMS Coil Placement Approaches for Targeting the Dorsolateral Prefrontal Cortex in Depressed Adolescents: An Electric Field Modeling Study
Deng, Zhi‐De , Robins, Pei L. , Dannhauer, Moritz , Haugen, Laura M., Port, John D. , Croarkin, Paul E. , Croarkin, Paul E , Port, John D

Biomedicines | August 21, 2023 | Volume: 11 | Issue: 8 | Pages: 2320

10.3390/biomedicines11082320 Get It

High-frequency repetitive transcranial magnetic stimulation (rTMS) to the left dorsolateral prefrontal cortex (L-DLPFC) shows promise as a treatment for treatment-resistant depression in adolescents. Conventional rTMS coil placement strategies include the 5 cm, the Beam F3, and the magnetic resonance imaging (MRI) neuronavigation methods. The purpose of this study was to use electric field (E-field) models to compare the three targeting approaches to a computational E-field optimization coil placement method in depressed adolescents. Ten depressed adolescents (4 females, age: 15.9±1.1) participated in an open-label rTMS treatment study and were offered MRI-guided rTMS five times per week over 6–8 weeks. Head models were generated based on individual MRI images, and E-fields were simulated for the four targeting approaches. Results showed a significant difference in the induced E-fields at the L-DLPFC between the four targeting methods (χ2=24.7, p<0.001). Post hoc pairwise comparisons showed that there was a significant difference between any two of the targeting methods (Holm adjusted p<0.05), with the 5 cm rule producing the weakest E-field (46.0±17.4V/m), followed by the F3 method (87.4±35.4V/m), followed by MRI-guided (112.1±14.6V/m), and followed by the computational approach (130.1±18.1V/m). Variance analysis showed that there was a significant difference in sample variance between the groups (K2=8.0, p<0.05), with F3 having the largest variance. Participants who completed the full course of treatment had median E-fields correlated with depression symptom improvement (r=−0.77, p<0.05). E-field models revealed limitations of scalp-based methods compared to MRI guidance, suggesting computational optimization could enhance dose delivery to the target.
Upper Cervical Cord Volume and Its Association with Brain Metrics in MS (P10-3.012)
Neyal, Nur , Son, Jiye , Atkinson, Elizabeth J. , Kantarci, Kejal , Kantarci, Orhun H. , Kantarci, Kejal , Schwarz, Christopher G. , Morrison, Holly, Port, John D. , Zeydan, Burcu

Neurology | April 28, 2023 | Volume: 100 | Issue: 17_supplement_2 | Pages: No page available

10.1212/wnl.0000000000203950 Get It

Long‐term clinical, imaging and cognitive outcomes association with MS immunopathology
Tillema, Jan‐Mendelt , Guo, Yong , Weigand, Stephen D. , Metz, Imke , Brück, Wolfgang , Giraldo‐Chica, Mónica , Lucchinetti, Claudia F. , Tobin, William Oliver, Metz, Imke , Lucchinetti, Claudia F , Kalinowska, Alicja , Tobin, W. Oliver , Lassmann, Hans , Port, John D.

Annals of Clinical and Translational Neurology | February 10, 2023 | Volume: 10 | Issue: 3 | Pages: 339-352

10.1002/acn3.51723 Get It

AbstractObjectiveIn this observational study on a cohort of biopsy‐proven central nervous system demyelinating disease consistent with MS, we examined the relationship between early‐active demyelinating lesion immunopattern (IP) with subsequent clinical course, radiographic progression, and cognitive function.MethodsSeventy‐five patients had at least one early‐active lesion on biopsy and were pathologically classified into three immunopatterns based on published criteria. The median time from biopsy at follow‐up was 11 years, median age at biopsy ‐ 41, EDSS ‐ 4.0. At last follow‐up, the median age was 50, EDSS ‐ 3.0. Clinical examination, cognitive assessment (CogState battery), and 3‐Tesla‐MRI (MPRAGE/FLAIR/T2/DIR/PSIR/DTI) were obtained.ResultsIP‐I was identified in 14/75 (19%), IP‐II was identified in 41/75 (56%), and IP‐III was identified in 18/75 (25%) patients. Patients did not differ significantly by immunopattern in clinical measures at onset or last follow‐up. The proportions of disease courses after a median of 11 years were similar across immunopatterns, relapsing–remitting being most common (63%), followed by monophasic (32%). No differences in volumetric or DTI measures were found. CogState performance was similar for most tasks. A slight yet statistically significant difference was identified for episodic memory scores, with IP‐III patients recalling one word less on average.InterpretationIn this study, immunopathological heterogeneity of early‐active MS lesions identified at biopsy does not correlate with different long‐term clinical, neuroimaging or cognitive outcomes. This could be explained by the fact that while active white matter lesions are pathological substrates for relapses, MS progression is driven by mechanisms converging across immunopatterns, regardless of pathogenic mechanisms driving the acute demyelinated plaque.
CTNI-23. PRELIMINARY SAFETY AND PHARMACOKINETICS DATA FOR A PHASE 1B TRIAL OF TELAGLENASTAT IN COMBINATION WITH RADIATION THERAPY AND TEMOZOLOMIDE IN PATIENTS WITH IDH-MUTANT GRADE 2/3 ASTROCYTOMA (NCI-10218)
Kizilbash, Sani H. , Sahebjam, Solmaz , Jaeckle, Kurt A. , Welch, Mary , Kong, Xiao–Tang , Holdhoff, Matthias , Lammers, Anita, Remick, Adam, Allred, Jacob B., McBrayer, Samuel K. , Kunos, Charles A., Adjei, Alex A. , Kizilbash, Sani H , Piccioni, David Eric , Villano, John L. , Reid, Joel M. , Port, John D. , Lanza, Ian R. , Shapiro, Geoffrey I.

Neuro-Oncology | November 14, 2022 | Volume: 24 | Issue: Supplement_7 | Pages: vii75-vii75

10.1093/neuonc/noac209.288 Get It

Abstract IDH mutant gliomas depend on glutaminase for glutamate/glutathione generation from glutamine because R-2-hydroxyglutarate inhibits branched chain amino acid transaminase mediated glutamate biosynthesis. Telaglenastat (CB-839 HCl) is a potent glutaminase-1 specific inhibitor which depletes tumor glutamate in orthotopic IDH mutant glioma PDX models and extends survival in these orthotopic models when added to radiation/temozolomide. NCI-10218 (NCT03528642) is a phase I clinical trial investigating the safety and tolerability of telaglenastat administered orally concurrently with standard doses of radiation (50.4 Gy, grade 2; 59.4 Gy, grade 3) and temozolomide (75 mg/m2 orally daily) in patients (age 16+) with previously untreated IDH mutant grade 2/3 astrocytoma. Telaglenastat dose was escalated in cohorts (400-800 mg twice daily) based on a standard 3 + 3 design to determine the recommended phase 2 dose (RP2D). Toxicities were graded per CTCAE v5.0. An expansion cohort additionally incorporated a seven-day run-in of telaglenastat monotherapy at RP2D prior to radiation to evaluate the pharmacodynamic impact of telaglenastat on plasma and tumor metabolites. 23 patients with IDH mutant astrocytoma (WHO grade 2, n = 5; WHO grade 3, n = 18) were accrued between December 2018 and January 2022 (Dose Escalation: 16; Dose Expansion: 7). Median age was 32 years (range 23-69 years). 61% were male and 70% were ECOG 0. No dose-limiting toxicities were observed. Grade 3/4 adverse events (independent of attribution) included: lymphopenia (3), neutropenia (2), leukocytosis (2), alanine transaminase elevation (2), thrombocytopenia (1), leukopenia (1), maculopapular rash (1), hyperglycemia (1), hyponatremia (1). The RP2D of concurrent telaglenastat was defined as 800 mg twice daily. Following peak absorption on Day 15 at RP2D, the mean (%CV) terminal elimination half-life in the plasma was 4.2 (53.5%) hours (range 2.1-7.1 hours). The Cmax, Tmax, oral clearance, and AUC were 1496 ng/mL, 4.0 hr, 93.6 L/hr/m2, and 7430 ng/mL*hr, respectively.