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There is evidence that glycemic fluctuations trigger vascular-mediated dysfunction in both the retina and the striatopallidal regions in patients with diabetes. The latter is associated with a variety of hyperkinetic disorders that are rare but disabling and potentially preventable. We conducted a systematic review of the potential association between diabetic retinopathy and the risk and prognosis of hyperkinetic disorders in patients with diabetes. We identified a total of 461 articles and 147 were eligible for review. Nine out of 147 articles (6.12%) reported 13 patients with information on diabetic retinopathy. Glycemic fluctuations were present at onset in 10 patients (77%) and retinopathy was present in nine of them (69.23%). The degree of retinopathy was reported in four patients. Two had severe, bilateral proliferative retinopathy, one had moderate-to-severe non-proliferative retinopathy and one had non-proliferative retinopathy. In the nine patients with retinopathy, hyperkinesia persisted, required higher doses of dopamine receptor antagonists or deep brain stimulation. Retinopathy was absent in four cases (30.77%). In these patients, hyperkinesia resolved spontaneously or with lower doses of dopamine receptor antagonists. Diabetic retinopathy could be an indirect marker of striatopallidal microangiopathy in patients with diabetes. The severity of retinopathy may be associated with increased risk or worse prognosis for patients who develop hyperkinetic disorders of the diabetic striatopathy spectrum. Early detection of retinopathy could identify patients in which avoiding glycemic fluctuations may prevent the development of striatopathy and hyperkinetic disorders.

Alterations in the peripheral inflammatory profile and white matter (WM) deterioration are frequent in Major Depressive Disorder (MDD). The present study applies free-water imaging to investigate the relationship between altered peripheral inflammation and WM microstructure and their predictive value in determining response to ketamine treatment in MDD.Ten individuals with MDD underwent diffusion-weighted magnetic resonance imaging and a blood-draw before and 24 h after ketamine infusion. We utilized MANCOVAs and ANCOVAs to compare tissue-specific fractional anisotropy (FAThe MDD group exhibited an increased IL-8/IL-10 ratio compared to controls at baseline (p = .040), which positively correlated with average FW across regions of interest (p = .013). Ketamine responders demonstrated higher baseline FAThe small sample size and short follow-up period limit the conclusion regarding the longer-term effects of ketamine in MDD.This pilot study provides evidence for the role of inflammation in MDD by illustrating an association between peripheral inflammation and WM microstructure. Additionally, we demonstrate that free-water diffusion-weighted imaging might be a valuable tool to determine which individuals with MDD benefit from the anti-inflammatory mediated effects of ketamine treatment.

Medical education has drastically transformed during the COVID-19 pandemic. Measures such as adopting telemedicine visits, minimizing the number of trainees on service, discontinuing external rotations, and converting in-person to online didactics have been broadly and swiftly implemented. While these innovations have promoted greater interconnectivity amongst institutions and made continuing medical education possible, international exchange programs in medical education are still largely disrupted. In response to the changing guidelines and restrictions necessitated by the COVID-19 pandemic, the authors used Kern's six-step approach to design and implement a virtual curriculum to replace the in-person activities of the 2020-2021 Neurology Peru-Rochester exchange program (NeuroPro). Twenty-seven trainees participated in this virtual adaptation. The average daily attendance was ≥85% and the program was rated 9/10 on average in a feedback survey (63% response rate). The median percentage of correct answers during the pre-test was 64% and it increased to 79% during the post-test (P = 0.003). Virtual adaptation of international exchange programs in medical education is feasible to safely continue international collaborative efforts to promote symbiotic building of local expertise and cross-cultural exchange during the ongoing COVID-19 pandemic and beyond.

Progress in neurodevelopmental brain research has been achieved through the use of animal models. Such models not only help understanding biological changes that govern brain development, maturation and aging, but are also essential for identifying possible mechanisms of neurodevelopmental and age-related chronic disorders, and to evaluate possible interventions with potential relevance to human disease. Genetic relationship of rhesus monkeys to humans makes those animals a great candidate for such models. With the typical lifespan of 25 years, they undergo cognitive maturation and aging that is similar to this observed in humans. Quantitative structural neuroimaging has been proposed as one of the candidate in vivo biomarkers for tracking white matter brain maturation and aging. While lifespan trajectories of white matter changes have been mapped in humans, such knowledge is not available for nonhuman primates. Here, we analyze and model lifespan trajectories of white matter microstructure using in vivo diffusion imaging in a sample of 44 rhesus monkeys. We report quantitative parameters (including slopes and peaks) of lifespan trajectories for 8 individual white matter tracts. We show different trajectories for cellular and extracellular microstructural imaging components that are associated with white matter maturation and aging, and discuss similarities and differences between those in humans and rhesus monkeys, the importance of our findings, and future directions for the field. Significance Statement: Quantitative structural neuroimaging has been proposed as one of the candidate in vivo biomarkers for tracking brain maturation and aging. While lifespan trajectories of structural white matter changes have been mapped in humans, such knowledge is not available for rhesus monkeys. We present here results of the analysis and modeling of the lifespan trajectories of white matter microstructure using in vivo diffusion imaging in a sample of 44 rhesus monkeys (age 4-27). We report and anatomically map lifespan changes related to cellular and extracellular microstructural components that are associated with white matter maturation and aging.

Several prominent theories of schizophrenia suggest that structural white matter pathologies may follow a developmental, maturational, and/or degenerative process. However, a lack of lifespan studies has precluded verification of these theories. Here, we analyze the largest sample of carefully harmonized diffusion MRI data to comprehensively characterize age-related white matter trajectories, as measured by fractional anisotropy (FA), across the course of schizophrenia. Our analysis comprises diffusion scans of 600 schizophrenia patients and 492 healthy controls at different illness stages and ages (14-65 years), which were gathered from 13 sites. We determined the pattern of age-related FA changes by cross-sectionally assessing the timing of the structural neuropathology associated with schizophrenia. Quadratic curves were used to model between-group FA differences across whole-brain white matter and fiber tracts at each age; fiber tracts were then clustered according to both the effect-sizes and pattern of lifespan white matter FA differences. In whole-brain white matter, FA was significantly lower across the lifespan (up to 7%; p

BACKGROUND: Evidence for age related brain white matter (WM) abnormalities in schizophrenia (SZ) has been observed using MRI, and interpreted by various studies as reflecting either developmental, maturational and/or degenerative pathology. Such conflicting findings, mostly due to lack of longitudinal data and statistical power, have hindered consensus on patterns and trajectories of brain dysfunction in SZ. ‘Big Data’ provides a new and powerful means to identify subtle abnormalities across the course of SZ. We have accumulated and processed, what we believe the biggest, to-date, sample of thoughtfully harmonized diffusion MRI (dMRI) cross sectional data, and performed the study aimed at comprehensively characterizing age-related WM changes (trajectories) through the course of SZ. METHODS: Our dMRI data comprises a total of 1092 participants, aged between 14 and 65. This includes 600 individuals with SZ at different illness stages (383 males, 217 females, age: 31.3+/- 12) and 492 healthy controls-HC (275 males, 217 females, age: 29.8+/-13), from 13 different sites. Preprocessing and dMRI data harmonization based on the rotation invariant spherical harmonics were used to remove the nonlinear scanner and sequence differences across sites. All harmonized data was registered to a common template. Fractional Anisotropy (FA) for Whole Brain (WB) and 14 individual WM regions of interest (ROIs) were computed using a probabilistic tractography atlas. We modeled FA changes over age by quadratic curves (the best fitted model: highest adjusted r^2) and fitted separately to SZ and HC. Peak age and upper and lower bounds of the model were estimated after 5000 bootstraps. FA% differences were modeled at each age between SZ and HC for WB and each ROI, while sex was treated as a confound. The effect sizes (Cohen’s d) between SZ and HC were also computed at each age. Finally, WM pathologies (i.e. based on between-group differences) were clustered into three groups according to d occurring along trajectory using kmeans. RESULTS: In WB, FA was lower in SZ comparing to HC at each age, but the percentage differences as well as d varied significantly by age (range of %FA change = [1.5 7], d = [.5 1.8]). Also, WB peaks of FA differed between groups, observed at the age of 33 in HC, shifted to the age of 27 in SZ. Three groups emerged from examining the degree of WM pathology across the age trajectories in ROIs, characterized by: 1) .3

Introduction Disruptions in homeostatic and hedonic food motivation are proposed to underlie anorexia nervosa (AN) and atypical AN, restrictive eating disorders which commonly onset in puberty. Ghrelin, a neuroprotective hormone that drives hedonic eating is increased in AN and is expressed in the hippocampus. White matter (WM) undergoes significant change during puberty in regions involved in food motivation, particularly WM tracts connected with the hippocampus. The association between ghrelin and WM region of interest (ROI) with hippocampal connections in restrictive eating disorders, particularly in adolescence during key neurodevelopmental growth, is unknown. Methods We evaluated fasting plasma ghrelin and WM microstructure (measured by free-water corrected fractional anisotropy (FA-t)) in WM ROIs with hippocampal connections - the fornix and the hippocampal portion of the cingulum - in 56 adolescent females (age range: 11.9 - 22.1 y; mean: 19.0 y) with low-weight eating disorders including AN and atypical AN (N = 36) and healthy controls (N = 20). Results FA-t in the fornix or hippocampal portion of the fornix did not differ between groups. Ghrelin was higher in AN/atypical AN vs. HC and was positively correlated with puberty stage in the AN/atypical AN group, but not the HC group. The correlation between ghrelin and FA-t in the fornix was significantly different in females with AN/atypical AN compared to controls. In AN/atypical AN, pubertal stage moderated the relation between fasting plasma ghrelin and FA-t in the fornix: higher fasting ghrelin was associated with lower FA-t in the fornix in late-post-puberty, but was not associated with FA-t in the early to mid stages of puberty. Conclusions In post-pubertal females with low-weight AN/atypical AN, higher levels of ghrelin are associated with lower FA-t in the fornix. This relationship is not evident in the early to mid stages of puberty in AN/atypical AN or in HC, and may reflect a lack of possible neuroprotective effects of ghrelin in late-post puberty only. Understanding the effects of ghrelin on WM microstructure longitudinally and following recovery from AN/Atypical AN and how this differs across pubertal stages will be an important next step. These findings could ultimately inform treatment staging and aid in diagnosis and detection of AN/atypical AN.

To determine whether localization and size are related to the presence of high-grade dysplasia of colon adenomas in patients of a Peruvian hospital.This is a descriptive transversal study. We checked colonoscopyreports of 2014-2015 years of Hospital Daniel Alcides Carrion, we included the polyps found in patients older than 18 years old, and excluded reports from patients with colorectal cancer, an antecedent of oncological surgery, inflammatory bowel disease and polyposis (6 or more). We used data based on localization (proximal and distal colon, based on the splenic angle), size (less than 10 mm and 10 mm or more), shape (pediculate and sessile) and grade of dysplasia (low and high-grade). We calculated the strength of association by OR, and we determined whether there was association by Chi-square test with a significance value less than 0.05.We reviewed a total of 1710 of colonoscopy reports, 378 patients had polyps, so the adenoma detection rate was 22.1%. There were 458 polyps, from which 254 were adenomas. From these adenomas, we found an association between distal colon localization and high-grade dysplasia (OR 2.68 IC 1.12-6.42, p0.05); likewise, there was an association between the size of the adenomas and high-grade dysplasia (OR 7.75 IC 3.05-19.69, p0.05). We did not find any association between the shape and grade of dysplasia.This study concludes that there is an association between the size of 10 mm or more and localization in the distal colon with high-grade dysplasia of adenomas.