Reduction of extramedullary erythropoiesis and amelioration of anemia in a ß-thalassemia patient treated with thalidomide.

ß-thalassemia patient treated with thalidomide: dimensional reduction of EMH foci (MRI evaluation) and reduction of hematological responce at follow-up.

Imaging of ring-shaped lateral ventricular nodules (RSLVNs).

Ring-shaped lateral ventricular nodules (RSLVN) are small and round nodules attached on the ependyma of lateral ventricles with unknown nature. They are considered "leave me alone lesions" and differential diagnosis includes subependymal grey matter heterotopia, subependymomas, subependymal hamartomas, and subependymal giant cell astrocytomas. In this short article, we report imaging findings of RSLNVs discovered in five patients, underlining the pivotal role of neuroimaging in the diagnostic path.

Chronic stress facilitates bursting electrical activity in pituitary corticotrophs.

Coordination of an appropriate stress response is dependent upon anterior pituitary corticotroph excitability in response to hypothalamic secretagogues and glucocorticoid negative feedback. A key determinant of corticotroph excitability is large conductance calcium- and voltage-activated (BK) potassium channels that are critical for promoting corticotrophin-releasing hormone (CRH)-induced bursting that enhances adrenocorticotrophic hormone secretion. Previous studies revealed hypothalamic-pituitary-adrenal axis hyperexcitability following chronic stress (CS) is partly a function of increased corticotroph output. Thus, we hypothesise that chronic stress promotes corticotroph excitability through a BK-dependent mechanism. Corticotrophs from CS mice displayed significant increase in spontaneous bursting, which was suppressed by the BK blocker paxilline. Mathematical modelling reveals that the time constant of BK channel activation, plus properties and proportion of BK channels functionally coupled to L-type Ca2+ channels determines bursting activity. Surprisingly, CS corticotrophs (but not unstressed) display CRH-induced bursting even when the majority of BK channels are inhibited by paxilline, which modelling suggests is a consequence of the stochastic behaviour of a small number of BK channels coupled to L-type Ca2+ channels. Our data reveal that changes in the stochastic behaviour of a small number of BK channels can finely tune corticotroph excitability through stress-induced changes in BK channel properties. Importantly, regulation of BK channel function is highly context dependent allowing dynamic control of corticotroph excitability over a large range of time domains and physiological challenges in health and disease. This is likely to occur in other BK-expressing endocrine cells, with important implications for the physiological processes they regulate and the potential for therapy. KEY POINTS: Chronic stress (CS) is predicted to modify the electrical excitability of anterior pituitary corticotrophs. Electrophysiological recordings from isolated corticotrophs from CS male mice display spontaneous electrical bursting behaviour compared to the tonic spiking behaviour of unstressed corticotrophs. The increased spontaneous bursting from CS corticotrophs is BK-dependent and mathematical modelling reveals that the time constant of activation, properties and proportion of BK channels functionally coupled to L-type calcium channels determines the promotion of bursting activity. CS (but not unstressed) corticotrophs display corticotrophin-releasing hormone-induced bursting even when the majority of BK channels are pharmacologically inhibited, which can be explained by the stochastic behaviour of a small number of BK channels with distinct properties. Corticotroph excitability can be finely tuned by the stochastic behaviour of a small number of BK channels dependent on their properties and functional co-localisation with L-type calcium channels to control corticotroph excitability over diverse time domains and physiological challenges.

Single-cell analyses and machine learning define hematopoietic progenitor and HSC-like cells derived from human PSCs.

Hematopoietic stem and progenitor cells (HSPCs) develop in distinct waves at various anatomical sites during embryonic development. The in vitro differentiation of human pluripotent stem cells (hPSCs) recapitulates some of these processes; however, it has proven difficult to generate functional hematopoietic stem cells (HSCs). To define the dynamics and heterogeneity of HSPCs that can be generated in vitro from hPSCs, we explored single-cell RNA sequencing (scRNAseq) in combination with single-cell protein expression analysis. Bioinformatics analyses and functional validation defined the transcriptomes of naïve progenitors and erythroid-, megakaryocyte-, and leukocyte-committed progenitors, and we identified CD44, CD326, ICAM2/CD9, and CD18, respectively, as markers of these progenitors. Using an artificial neural network that we trained on scRNAseq derived from human fetal liver, we identified a wide range of hPSC-derived HSPCs phenotypes, including a small group classified as HSCs. This transient HSC-like population decreased as differentiation proceeded, and was completely missing in the data set that had been generated using cells selected on the basis of CD43 expression. By comparing the single-cell transcriptome of in vitro-generated HSC-like cells with those generated within the fetal liver, we identified transcription factors and molecular pathways that can be explored in the future to improve the in vitro production of HSCs.

Imaging of cerebral amyloid angiopathy-related inflammation (CAA-ri).

CAA-ri is a reversible and rare encephalopathy that may manifest in patients with CAA. In this short article, we describe CT and MRI findings of CAA-ri in a 67-year-old man presented to emergency with sudden aphasia and acute cognitive dysfunction, underlining the pivotal role of neuroimaging in the diagnostic path.

Internal carotid artery dissection related to abnormalities of styloid process: is it only a matter of length?

INTRODUCTION: Vascular Eagle syndrome, due to impingement of the extracranial internal carotid artery (ICA) by the styloid process (SP), is an uncommon and not yet widely recognized cause of ICA dissection. Up to now, this diagnosis is still presumptive, based mainly on the length of the SP. However, given the discrepancy between the much higher prevalence of an elongated SP in the population compared to the reported rate of Eagle syndrome, other anatomical factors beyond the length itself of this bony structure seem to be involved. MATERIAL AND METHODS: We performed a retrospective single center case-control study of ICA dissection related to abnormalities of styloid process and age- and sex-matched controls affected by ICA dissection not related to abnormal relationship with the styloid process. In our work instead of considering SP length as the main criteria to differentiate the two groups, we decided to consider styloid process-internal carotid artery distance (at the dissection point) as the main factor to define a styloid process related dissection (SPRD). In fact in some patients, the distance between the dissected artery and the bony prominence was virtual. RESULTS: Our study showed that in patients with SPRD the styloid process angulation on the coronal plane tends to be more acute and that styloid process-C1 distance is significantly shorter at the side of the dissection. This data reinforces the idea that ICA dissection risk in the vascular Eagle syndrome has probably a multifactorial pathogenesis.

Head CT in centenarians: emergency and non-emergency findings.

INTRODUCTION: Our retrospective study evaluates head CTs performed in our Hospital in the last 11 years (2009-2019) in centenarian patients. OBJECTIVES: To estimate the correlation between reasons for examination and CT findings in emergency and to evaluate if there was the expected involution of the brain by analyzing some non-emergency neuroradiological parameters (NENP). MATERIAL AND METHODS: 62 Head CTs performed on patients aged 100 and over were reviewed. They were evaluated emergency CT findings and NENP (leukoencephalopathy, enlargement of the ventricular volume, presence of vascular calcifications). For comparison, NENP were also assessed in two relatively younger populations of 62 patients aged between 65-70 (called "65-70") and 85-90 ("85-90"). RESULTS: In cases of suspected traumatic brain lesions, 11.9% (n = 5/42) of centenarians showed a cerebral bleeding; as concerns suspected stroke we found a higher concordance between clinical suspicion and CT features, 46.6% (n = 7/15). As regards NENP, no significant differences were found with respect to the "85-90" population in terms of severity of leukoencephalopathy, enlargement of the ventricular volume and presence of vascular calcifications. CONCLUSIONS: In emergency, CT plays a pivotal role in defining an immediate diagnosis and from a medico-legal point of view, resulting together with clinical observation the main strategy in the management of centenarians. By the analysis of NENP we may support that centenarians' brains on CT are similar to those of "85-90".

Calcified brain metastases may be more frequent than normally considered.

OBJECTIVES: To verify the incidence of calcified brain metastases (CBM), illustrating the different presentation patterns and histology of primary tumor. METHODS: A series of 1002 consecutive brain computed tomography (CT) scans of patients with known primary tumors was retrospectively assessed. CBM were defined by the presence of calcification within intra-axial-enhancing lesions; identification of CBM was based on visual examination and ROI analysis (> 85 Hounsfield units). Also, calcifications in the primary tumor of all patients with brain metastases were evaluated. In CBM patients, we investigated the type of calcifications (punctate, nodular, cluster, ring, coarse), the histology of primary tumor, and if a previous RT was performed. RESULTS: Among 190 (18.9%) patients with brain metastatic disease, 34 presented with CBM (17.9%). Sixteen patients were previously treated with RT, while 18 presented calcifications ab initio (9.5% of all brain metastases). The majority of patients with CBM had a primitive lung adenocarcinoma (56%), followed by breast ductal invasive carcinoma (20%) and small cell lung carcinoma (11.8%). CBM were single in 44.1% of patients and multiple in 55.9%. With regard to the type of calcifications, the majority of CBM were punctate, without specific correlations between calcification type and histology of primary tumor. No patients with ab initio CBM had calcifications in primary tumor. CONCLUSION: In conclusion, our data show that CBM are more common than usually thought, showing an incidence of 9.5% ab initio in patients with brain metastases. This study underlines that neuroradiologists should not overlook intraparenchymal brain calcifications, especially in oncologic patients. KEY POINTS: • Among the differential diagnosis of brain intraparenchymal calcifications, metastases are considered uncommon and found predominantly in patients treated with radiotherapy (RT). • Our data show that CBM are more common than usually thought, showing an incidence of 9.5% ab initio in patients with brain metastases. • A proportion of intraparenchymal brain calcifications, especially in oncologic patients, might represent evolving lesions and neuroradiologists should not overlook them to avoid a delay in diagnosis and treatment.

Imaging of intracranial fat: from normal findings to pathology.

The presence of intracranial adipose tissue is often overlooked, although it may be detected in different physiological (dural sinuses or falx deposition of fat) and pathological (lipoma, dermoid cyst, subarachnoid fat dissemination) conditions. In this review, we illustrate various scenarios in which radiologists and neuroradiologists may encounter intracranial fat, providing a list of differential diagnosis.

Degree of microstructural changes within T1-SE versus T1-GE hypointense lesions in multiple sclerosis: relevance for the definition of "black holes".

OBJECTIVES: To retrospectively evaluate the different performances of T1-SE and T1-GE sequences in detecting hypointense lesions in multiple sclerosis (MS), to quantify the degree of microstructural damage within lesions and to correlate them with patient clinical status. METHODS: Sixty clinically isolated syndrome (CIS) and MS patients underwent brain magnetic resonance imaging (MRI) on 1.5-T and 3-T scanners. We identified T2 fluid-attenuated inversion recovery hyperintense lesions with no hypointense signal on T1-SE/T1-GE (a), hypointense lesions only on T1-GE (b), and hypointense lesions on both T1-SE and T1-GE sequences (c). We compared mean lesion number (LN) and volume (LV) identified on T1-SE and T1-GE sequences, correlating them with Expanded Disability Status Scale (EDSS); fractional anisotropy (FA) and mean diffusivity (MD) values inside each lesion type were extracted and normal-appearing white matter (NAWM). RESULTS: Thirty-five patients were female. Mean age was 39.2 (± 7.8); median EDSS was 3 (± 2). There were 23 CIS, 21 relapsing-remitting (RR), and 16 progressive MS. T1-GE and T1-SE LN and LV were significantly different (p < 0.001), both correlating with EDSS. Both FA and MD metrics resulted significantly different among the three lesion groups and NAWM (p < 0.001). FA and MD values extracted from (b) and (c) showed statistically significant differences (p < 0.001), while for (a) and (b), the differences were not significant (p = 0.31 for FA and p = 0.62 for MD). CONCLUSION: T1-SE hypointense lesions demonstrated a more pronounced degree of microstructural damage. T1-weighted sequence type must be more carefully evaluated in clinical and research settings. KEY POINTS: • T1-weighted spin-echo (T1-SE) images detect chronic hypointense lesions (so called black holes) associated with more severe microstructural changes. • In the last years, three-dimensional (3D) T1-weighted gradient-echo (T1-GE) sequences are often utilized in lieu of T1-SE acquisition, more so at 3 T or higher fields. • T1-weighted sequence type must be more carefully evaluated in clinical and research settings in the definition of "black holes" in MS, in order to avoid the overestimation of the effective severe tissue damage.

Multiple-scale neuroendocrine signals connect brain and pituitary hormone rhythms.

Small assemblies of hypothalamic "parvocellular" neurons release their neuroendocrine signals at the median eminence (ME) to control long-lasting pituitary hormone rhythms essential for homeostasis. How such rapid hypothalamic neurotransmission leads to slowly evolving hormonal signals remains unknown. Here, we show that the temporal organization of dopamine (DA) release events in freely behaving animals relies on a set of characteristic features that are adapted to the dynamic dopaminergic control of pituitary prolactin secretion, a key reproductive hormone. First, locally generated DA release signals are organized over more than four orders of magnitude (0.001 Hz-10 Hz). Second, these DA events are finely tuned within and between frequency domains as building blocks that recur over days to weeks. Third, an integration time window is detected across the ME and consists of high-frequency DA discharges that are coordinated within the minutes range. Thus, a hierarchical combination of time-scaled neuroendocrine signals displays local-global integration to connect brain-pituitary rhythms and pace hormone secretion.

Imaging of extraventricular neurocytoma: a systematic literature review.

OBJECTIVE: Extraventricular neurocytoma (EVN) was firstly described in 1997. The current literature regarding imaging of EVN is limited to sporadic case reports and case series. EVN is still poorly considered in the differential diagnosis by neuroradiologists, thus diagnosis remains challenging. In this systematic review, we summarize and discuss computed tomography (CT) and magnetic resonance imaging (MRI) features of EVN cases described in the literature, in order to provide useful informations to neuroradiologists. To the best of our knowledge, this is the most extensive review about imaging of EVN. MATERIALS AND METHODS: A systematic review of the literature about imaging of EVN cases was done. Only case reports or case series in which imaging (CT and/or MRI) features were deeply described were included in the revision. Eligibility of studies was assessed independently by two authors and any disagreements resolved by discussion. RESULTS: Our search strategy revealed 224 articles. After implementation of inclusion and exclusion criteria, 35 studies were considered, and a total of 79 cases of EVN were analyzed. CONCLUSION: EVN has not specific characteristics, with a large and variable imaging spectrum. Usually it appears as a large tumor, with diameters superior to 40 mm, frequently involving the frontal lobe. CT density and MRI signal intensity typically mirror the presence of cystic, solid, or calcified elements; contrast enhancement is visible in 87% of cases. Today, diagnosis of EVN with only imaging techniques is not univocal; neuroradiologists can only suspect this type of lesion, while the definitive diagnosis remains histological.

Pre-operative Renal Artery Embolization in Laparoscopic Radical and Partial Nephrectomy: A Multidisciplinary Approach to Renal Tumors.

BACKGROUND: Despite being widely adopted, the laparoscopic approach to radical and partial nephrectomy is still burdened by high rates of hemorrhagic complications, which require blood transfusions and conversion to open surgery with increased morbidity. While pre-operative renal artery embolization (PRAE) can prevent intraoperative blood loss and vascular injuries, its prophylactic use is still a matter of debate. This study evaluated the safety and efficacy of PRAE in overcoming the main pitfalls of laparoscopy, which are related to the absence of tactile feedback. METHODS: Data from 48 patients who underwent laparoscopic nephrectomy for cancer (34 laparoscopic radical nephrectomy (LRN) and 14 "off-clamp" laparoscopic partial nephrectomy (LPN) after selective and superselective PRAE, respectively) were retrospectively evaluated. RESULTS: The overall median blood loss was 50 ml and only 2 patients (4%) required one unit of blood products. While conversion to open surgery was not required in the LPN group, one case in the LRN group was converted to open surgery due to intraoperative incoercible bleeding from an unrecognized, and thus not embolized, aberrant inferior polar artery. Post-embolization syndrome occurred in 7 patients (15%), resulting in mild flank pain and nausea. No patients in the LPN group experienced new onset of acute renal failure. CONCLUSION: Our experience supports pre-operative renal embolization as a safe, minimally invasive procedure that is effective for reducing perioperative bleeding in the laparoscopic setting.

Horseshoe adrenal gland associated with spinal and vascular anomalies.

Horseshoe (or butterfly) adrenal gland (HAG) is an exceedingly rare congenital abnormality compared to horseshoe kidney. Here we present computed tomography findings of HAG in a 70-year-old man, associated with some spinal and vascular abnormalities; in addition, a brief review of HAG in adult people is presented. In our case, spinal anomalies included a severe scoliosis, a "butterfly" deformation of Th9 vertebra and the presence of a "split lumbosacral thecal sac" at L5 level. As regards, vascular anomalies, they were noted: the origin of the left common carotid artery from the innominate artery and the absence of celiac trunk with separate origin of three branches directly off the aorta (a splenic artery, a left gastrohepatic trunk and a right hepatic-pancreaticoduodenal artery).

Loss of eIF4E Phosphorylation Engenders Depression-like Behaviors via Selective mRNA Translation.

The MAPK/ERK (mitogen-activated protein kinases/extracellular signal-regulated kinase) pathway is a cardinal regulator of synaptic plasticity, learning, and memory in the hippocampus. One of major endpoints of this signaling cascade is the 5' mRNA cap binding protein eIF4E (eukaryotic Initiation Factor 4E), which is phosphorylated on Ser 209 by MNK (MAPK-interacting protein kinases) and controls mRNA translation. The precise role of phospho-eIF4E in the brain is yet to be determined. Herein, we demonstrate that ablation of eIF4E phosphorylation in male mice (4Eki mice) does not impair long-term spatial or contextual fear memory, or the late phase of LTP. Using unbiased translational profiling in mouse brain, we show that phospho-eIF4E differentially regulates the translation of a subset of mRNAs linked to inflammation, the extracellular matrix, pituitary hormones, and the serotonin pathway. Consequently, 4Eki male mice display exaggerated inflammatory responses and reduced levels of serotonin, concomitant with depression and anxiety-like behaviors. Remarkably, eIF4E phosphorylation is required for the chronic antidepressant action of the selective serotonin reuptake inhibitor fluoxetine. Finally, we propose a novel phospho-eIF4E-dependent translational control mechanism in the brain, via the GAIT complex (gamma IFN activated inhibitor of translation). In summary, our work proposes a novel translational control mechanism involved in the regulation of inflammation and depression, which could be exploited to design novel therapeutics.SIGNIFICANCE STATEMENT We demonstrate that downstream of the MAPK (mitogen-activated protein kinase) pathway, eukaryotic Initiation Factor 4E (eIF4E) Ser209 phosphorylation is not required for classical forms of hippocampal LTP and memory. We reveal a novel role for eIF4E phosphorylation in inflammatory responses and depression-like behaviors. eIF4E phosphorylation is required for the chronic action of antidepressants, such as fluoxetine in mice. These phenotypes are accompanied by selective translation of extracellular matrix, pituitary hormones, and serotonin pathway genes, in eIF4E phospho-mutant mice. We also describe a previously unidentified translational control mechanism in the brain, whereby eIF4E phosphorylation is required for inhibiting the translation of gamma IFN activated inhibitor of translation element-containing mRNAs. These findings can be used to design novel therapeutics for depression.

Wrist and Hand Ultrasound: Reliability of Side-to-Side Comparisons of Very Small (<2-mm) Clinically Relevant Anatomic Structures.

OBJECTIVES: In ultrasound (US) examinations of clinically relevant very small structures of the wrist and hand, the healthy contralateral side can be used as a reference to identify subtle abnormalities. Intraindividual side-to-side variability must be minimal. The aim of this study was to assess the reliability of side-to-side US evaluations of very small structures of the wrist and hand. METHODS: Forty-one healthy volunteers were prospectively studied. Small structures of the wrist and hand were evaluated bilaterally by 2 musculoskeletal radiologists in separate sessions. The first annular pulleys of the second finger and the thumb, sagittal band of the third finger, extensor and flexor retinacula, ulnar collateral ligament of the thumb, radial collateral ligament of the second finger, and palmar cutaneous branches of the median and ulnar nerves were considered. To assess intra- and inter-reader agreement, 10 of 41 (24%) examinations were repeated. Nonparametric statistics were used. RESULTS: Data were not normally distributed (P > .001). Intra-reader agreement was κ = 0.674 (95% confidence interval [CI], 0.57-0.78), and inter-reader agreement was κ = 0.935 (95% CI, 0.92-0.95). The mean value ± SD for all of the structures was 0.78 ± 0.44 mm. The overall coefficient of variation was 9.8% ± 0.07%. The intraclass correlation coefficient was 0.97 (95% CI, 0.96-0.98). CONCLUSIONS: In clinical practice, the healthy contralateral side can be used as a reference during a real-time musculoskeletal US evaluation of small (<2-mm) structures.

Complementary actions of dopamine D2 receptor agonist and anti-vegf therapy on tumoral vessel normalization in a transgenic mouse model.

Angiogenesis contributes in multiple ways to disease progression in tumors and reduces treatment efficiency. Molecular therapies targeting Vegf signaling combined with chemotherapy or other drugs exhibit promising results to improve efficacy of treatment. Dopamine has been recently proposed to be a novel safe anti-angiogenic drug that stabilizes abnormal blood vessels and increases therapeutic efficacy. Here, we aimed to identify a treatment to normalize tumoral vessels and restore normal blood perfusion in tumor tissue with a Vegf receptor inhibitor and/or a ligand of dopamine G protein-coupled receptor D2 (D2R). Dopamine, via its action on D2R, is an endogenous effector of the pituitary gland, and we took advantage of this system to address this question. We have used a previously described Hmga2/T mouse model developing haemorrhagic prolactin-secreting adenomas. In mutant mice, blood vessels are profoundly altered in tumors, and an aberrant arterial vascularization develops leading to the loss of dopamine supply. D2R agonist treatment blocks tumor growth, induces regression of the aberrant blood supply and normalizes blood vessels. A chronic treatment is able to restore the altered balance between pro- and anti-angiogenic factors. Remarkably, an acute treatment induces an upregulation of the stabilizing factor Angiopoietin 1. An anti-Vegf therapy is also effective to restrain tumor growth and improves vascular remodeling. Importantly, only the combination treatment suppresses intratumoral hemorrhage and restores blood vessel perfusion, suggesting that it might represent an attractive therapy targeting tumor vasculature. Similar strategies targeting other ligands of GPCRs involved in angiogenesis may identify novel therapeutic opportunities for cancer.

Plasticity of hypothalamic dopamine neurons during lactation results in dissociation of electrical activity and release.

Tuberoinfundibular dopamine (TIDA) neurons are the central regulators of prolactin (PRL) secretion. Their extensive functional plasticity allows a change from low PRL secretion in the non-pregnant state to the condition of hyperprolactinemia that characterizes lactation. To allow this rise in PRL, TIDA neurons are thought to become unresponsive to PRL at lactation and functionally silenced. Here we show that, contrary to expectations, the electrical properties of the system were not modified during lactation and that the neurons remained electrically responsive to a PRL stimulus, with PRL inducing an acute increase in their firing rate during lactation that was identical to that seen in non-pregnant mice. Furthermore, we show a long-term organization of TIDA neuron electrical activity with an harmonization of their firing rates, which remains intact during lactation. However, PRL-induced secretion of dopamine (DA) at the median eminence was strongly blunted during lactation, at least in part attributable to lack of phosphorylation of tyrosine hydroxylase, the key enzyme involved in DA synthesis. We therefore conclude that lactation, rather than involving electrical silencing of TIDA neurons, represents a condition of decoupling between electrical activity at the cell body and DA secretion at the median eminence.

Exploring Compassion towards Laboratory Animals in UK- and China-Based Undergraduate Biomedical Sciences Students.

Taking a compassionate approach to the non-human animals used in biomedical research is in line with emerging ideas around a "culture of care". It is important to expose biomedical sciences students to the concept of a culture of care at an early stage and give them opportunities to explore related practices and ideas. However, there is no simple tool to explore biomedical sciences students' attitudes towards laboratory animals. Accordingly, there is little understanding of students' feelings towards these animals, or a means of quantifying potential changes to these feelings. We developed a 12-item questionnaire designed to explore compassion (the Laboratory Animal Compassion Scale; LACS) and used it with UK-based and China-based samples of undergraduate biomedical sciences students. In the same samples, we also explored a harm-benefit analysis task and students' beliefs regarding some mental characteristics of laboratory animals, then drew correlations with the quantitative measure of compassion. Compassion levels were stable across years of study and were not related to students' level of experience of working with laboratory animals. We observed a higher level of compassion in females versus males overall, and a higher level overall in the UK-based versus China-based sample. In a task pitting animal suffering against human wellbeing, students' compassion levels correlated negatively with their acceptance of animal suffering. Compassion levels correlated positively with a belief in animals being conscious and possessing emotions. These data are in line with studies that show compassion is gender- and nationality/culture-dependent, and points to links between compassion, beliefs, and choices.