Persistent 18F-FDG Brain PET Fronto-Temporal Hypometabolism and Cognitive Symptoms Two Years after SARS-CoV-2 Infection: A Case Report.

At least 10% of patients experience persistent symptoms after SARS-CoV-2 infection, a condition referred to as post-acute COVID-19, post-acute sequelae of SARS-CoV-2 infection (PASC), long COVID, long-haul COVID, long-term effects of COVID, post-COVID-19 and chronic COVID. In this report, we describe a case of persistent cognitive deficits developed after SARS-CoV-2 infection in a 40-year-old woman with a family history of early-onset Alzheimer's disease (EOAD) since her father was diagnosed with EOAD at the age of 50. We describe the clinical picture and workup, with special emphasis on the alterations of brain glucose metabolism evidenced by 18-fluoro-deoxy-glucose positron emission tomography (FDG-PET), which could be considered a useful marker of the presence and persistence of cognitive deficits.

Syrinx reduction due to spontaneous spinal cord tear: demonstration on 3 T MRI and review of the literature.

A holocord syringomyelia due to Chiari 1.5 malformation (CM) in a 12-year-old girl was serially imaged with 3 T MRI over 4 years. The serial MRI showed reduction in size of the syrinx, without any surgical intervention or CM improvement, but rather due to spontaneous spinal cord tear. The tear was clearly demonstrated by evidence of flow signal across the tear between syrinx and subarachnoid space at the upper thoracic level. The tear showed spontaneous closure at follow-up. A medullary tear has been described in the adult population as one of the putative causes of spontaneous syringomyelia reduction, but its clear demonstration with modern high-resolution MRI has not been reported in the paediatric population. Moreover, this is the first reported case of syrinx reduction due to spontaneous fissuration in a paediatric patient.

Report of a Case of Creutzfeldt-Jakob Disease With an Unusual Clinical Presentation.

We describe the clinical features, neuropsychological tests, laboratory, electroencephalography (EEG), magnetic resonance imaging (MRI) and positron emission tomography (PET) findings of a 59-year-old woman who presented to our Centre for cognitive impairment since few months, with language disturbances, particularly anomia, dyscalculia, and memory loss. The clinical and neuropsychological features were non-specific and overlapping with those of other rapidly progressing neurodegenerative disorders. However, brain MRI played a pivotal role in the diagnosis, showing cortical diffusion restriction, particularly in the parietal lobes and posterior cingulum, with sparing of the perirolandic cortex, typical of Creutzfeldt-Jakob disease (CJD). Brain MRI abnormalities were visible since the first evaluation and remained stable at 2 and 6 weeks follow up. Basal ganglia and thalami were never involved. PET showed left lateralized reduced glucose metabolism, with partial overlap with MRI signal abnormalities. Despite MRI were strongly indicative of CJD, clinical, laboratory and EEG findings did not fulfill the diagnostic criteria for CJD which applied at the time of clinical assessment. Indeed, neither myoclonus, visual or cerebellar signs or akinetic mutism were present. Also, the characteristic periodic sharp wave complexes were absent at baseline EEG, and the CSF assay for 14-3-3 was negative. We, therefore, performed a real-time quaking-induced conversion (RT-QuIC) assay on a frozen sample of corticospinal fluid (CSF), which showed a positive result. RT-QuIC is a prion protein conversion assay that has shown high diagnostic sensitivity and specificity for the diagnosis of CJD. RT-QuIC has been recently incorporated in the National CJD Research and Surveillance Unit and Center for Disease Control and Prevention (CDC) diagnostic criteria for CJD. The fatal evolution of the disease brought the patient to death 13 months after symptoms onset. Pathology proved the diagnosis of sporadic CJD, subtype MM/MV 2C.

Imaging in Spondylodiskitis.

Infections of the spine may involve different anatomic compartments, including intervertebral disks, vertebral bone, paraspinal soft tissues, epidural space, meninges, and spinal cord. This article focuses on the role of imaging in diagnosis and follow-up of infections of the intervertebral disk and vertebral bone, named respectively diskitis and spondylitis or vertebral osteomyelitis. Often, at the time of diagnosis, the infection already involves both structures; therefore the process is referred as spondylodiskitis. The discussion is extended to infections of paraspinal soft tissues and epidural space, which are commonly associated. Mention is made to the role of imaging in guiding minimally invasive biopsies of the spine in such conditions.

Prognostic value of CD109+ circulating endothelial cells in recurrent glioblastomas treated with bevacizumab and irinotecan.

BACKGROUND: Recent data suggest that circulating endothelial and progenitor cells (CECs and CEPs, respectively) may have predictive potential in cancer patients treated with bevacizumab, the antibody recognizing vascular endothelial growth factor (VEGF). Here we report on CECs and CEPs investigated in 68 patients affected by recurrent glioblastoma (rGBM) treated with bevacizumab and irinotecan and two Independent Datasets of rGBM patients respectively treated with bevacizumab alone (n=32, independent dataset A: IDA) and classical antiblastic chemotherapy (n=14, independent dataset B: IDB). METHODS: rGBM patients with KPS ≥50 were treated until progression, as defined by MRI with RANO criteria. CECs expressing CD109, a marker of tumor endothelial cells, as well as other CEC and CEP subtypes, were investigated by six-color flow cytometry. RESULTS: A baseline count of CD109+ CEC higher than 41.1/ml (1(st) quartile) was associated with increased progression free survival (PFS; 20 versus 9 weeks, P=0.008) and overall survival (OS; 32 versus 23 weeks, P=0.03). Longer PFS (25 versus 8 weeks, P=0.02) and OS (27 versus 17 weeks, P=0.03) were also confirmed in IDA with CD109+ CECs higher than 41.1/ml but not in IDB. Patients treated with bevacizumab with or without irinotecan that were free from MRI progression after two months of treatment had significant decrease of CD109+ CECs: median PFS was 19 weeks; median OS 29 weeks. The presence of two non-contiguous lesions (distant disease) at baseline was an independent predictor of shorter PFS and OS (P<0.001). CONCLUSIONS: Data encourage further studies on the predictive potential of CD109+ CECs in GBM patients treated with bevacizumab.

Central nervous system lymphoma occurring in a patient with neurofibromatosis type 1 (von Recklinghausen disease).

Neurofibromatosis type 1 (NF1) is an autosomal dominant disorder, which confers an increased risk of a wide range of cancers, and malignant tumors are the most common cause of death in individuals with NF1. Although in children with NF1, the most common neoplasms are optic nerve gliomas and brain tumors, an elevated risk of myeloid leukemia and an increased relative risk of acute lymphoblastic leukemia and non-Hodgkin lymphoma were reported. In adults with NF1, the relative risk of brain tumor is 100 times higher than in the general population. Cases of malignant lymphoma occurring in NF1 adult patients have been reported. However, the association between NF1 and lymphoproliferative diseases is still debated. We report a case of CNS primitive lymphoma in an adult patient who resulted positive for NF1 at genetic testing. At present, only one case of CNS lymphoma in an adult patient displaying clinical criteria for NF1 diagnosis has been reported.

Is there a common neuroanatomical substrate of language deficit between autism spectrum disorder and specific language impairment?

Discussion of an overlap between specific language impairment (SLI) and autism spectrum disorder (ASD) is on going. The most intriguing overlap between both phenotypes is the similarity in the observed language deficits described in SLI and a subgroup of ASD with co-occurring linguistic impairment, ASD-LI. Examining whether a similar neuroanatomical substrate underlies this phenotypical linguistic overlap, we studied the white matter microstructural properties of the superior longitudinal fascicle (SLF) of 19 ASD-LI adolescents (mean age 13.8 ± 1.6 years) and 21 age-matched controls and compared them with 13 SLI children (mean age 10.1 ± 0.4 years) and 12 age-matched controls. A linguistic profile assessment and a diffusion tensor imaging analysis of the SLF were performed. Linguistic testing revealed a mixed receptive-expressive disorder profile in both groups, confirming their overlap at phenotypical level. At neuroanatomical level, no significant differences in mean SLF fractional anisotropy (FA) and mean SLF apparent diffusion coefficient values between ASD-LI participants and controls were seen. By contrast, the mean SLF FA was significantly reduced in the SLI children as compared with their controls. The observation of structural SLF disturbances in SLI but not in ASD-LI suggests the existence of a different neuroanatomical substrate for the language deficits in both disorders.

Food intake-independent effects of CB1 antagonism on glucose and lipid metabolism.

Overactivity of the endocannabinoid system (ECS) has been linked to abdominal obesity and other risk factors for cardiovascular disease and type 2 diabetes. Conversely, administration of cannabinoid receptor type 1 (CB1) antagonists reduces adiposity in obese animals and humans. This effect is only in part secondary to the anorectic action of CB1 agonists. In order to assess the actions of CB1 antagonism on glucose homeostasis, diet-induced obese (DIO) rats received the CB1 antagonist rimonabant (10 mg/kg, intraperitoneally (IP)) or its vehicle for 4 weeks, or were pair-fed to the rimonabant-treated group for the same length of time. Rimonabant treatment transiently reduced food intake, while inducing body weight loss throughout the study. Rats receiving rimonabant had significantly less body fat and circulating leptin compared to both vehicle and pair-fed groups. Rimonabant, but not pair-feeding, also significantly decreased circulating nonesterified fatty acid (NEFA) and triacylglycerol (TG) levels, and reduced TG content in oxidative skeletal muscle. Although no effects were observed during a glucose tolerance test (GTT), rimonabant restored insulin sensitivity to that of chow-fed, lean controls during an insulin tolerance test (ITT). Conversely, a single dose of rimonabant to DIO rats had no acute effect on insulin sensitivity. These findings suggest that in diet-induced obesity, chronic CB1 antagonism causes weight loss and improves insulin sensitivity by diverting lipids from storage toward utilization. These effects are independent of the anorectic action of the drug.

Minireview: the brain as a molecular target for diabetic therapy.

Recent evidence highlights the important role of the brain in the control of glucose homeostasis. Hypothalamic centers sense the availability of peripheral nutrients via redundant and overlapping nutrient-induced peripheral signals such as leptin and insulin and via direct metabolic signaling. Responding to nutrient availability, these hypothalamic regions in turn exert a negative feedback not only on food intake but also on endogenous glucose production. Disruptions in the mechanisms of central nervous system nutrient sensing alter these homeostatic responses and contribute to the pathophysiology of obesity and type 2 diabetes. In this review, we discuss the neural and molecular pathways so far identified as possible targets for therapeutic intervention.

How the hypothalamus controls glucose production: an update.

Recent evidence highlights a crucial role of the brain in the control of glucose homeostasis. The hypothalamus senses and integrates signals of fuel abundance, such as circulating macronutrients (glucose and fatty acids) and nutrient-induced hormones (insulin and leptin). This, in turn, results in the activation of neural pathways that return circulating nutrients to baseline by reducing hepatic glucose production and food intake. In Type 2 diabetes and obesity, the ability of the brain to sense and respond to circulating signals is impaired. In this review, the neuroendocrine circuits that have recently been involved in the regulation of endogenous glucose production in rodents will be described. The study of these neural pathways promises to unveil new targets for the therapy of Type 2 diabetes and obesity.