Late onset neuromyelitis optica spectrum disorders (LONMOSD) from a nationwide Portuguese study: Anti-AQP4 positive, anti-MOG positive and seronegative subgroups.

INTRODUCTION: Several neuroimmunological disorders have distinct phenotypes according to the age of onset, as in multiple sclerosis or myasthenia gravis. It is also described that late onset NMOSD (LONMOSD) has a different phenotype. OBJECTIVE: To describe the clinical/demographic characteristics of the LONMOSD and distinguish them from those with early onset (EONMOSD). METHODS: From a nationwide Portuguese NMOSD study we analyzed the clinical/demographic characteristics of the LONMOSD. RESULTS: From the 180 Portuguese patients 45 had disease onset after 50 years old, 80% were female. 23 had anti-AQP4 antibodies (51.1%), 13 anti-MOG antibodies (28.9%) and 9 were double seronegative (20.0%). The most common presenting phenotypes in LONMOSD were transverse myelitis (53.3%) and optic neuritis (26.7%), without difference from EONMOSD (p = 0.074). The mean EDSS for LONMOSD was 6.0 (SD=2.8), after a mean follow-up time of 4.58 (SD=4.47) years, which was significantly greater than the mean EDSS of EONMOSD (3.25, SD=1.80)(p = 0.022). Anti-AQP4 antibodies positive LONMOSD patients had increased disability compared to anti-MOG antibodies positive LONMOSD (p = 0.022). The survival analysis showed a reduced time to use a cane for LONMOSD, irrespective of serostatus (p<0.001). CONCLUSIONS: LONMOSD has increased disability and faster progression, despite no differences in the presenting clinical phenotype were seen in our cohort.

TyPed study: Natalizumab for the treatment of pediatric-onset multiple sclerosis in Portugal.

BACKGROUND: A significant proportion of pediatric-onset multiple sclerosis (POMS) patients do not respond to first-line disease-modifying therapies. Clinical trials showed that natalizumab is effective and safe in adults, but there are limited clinical trial data for children. Natalizumab is currently prescribed off-label for POMS. We aimed to characterize the effectiveness, safety and tolerability of natalizumab in all POMS cases treated in Portugal (from 2007 to 2018). METHODS: Data from clinical records were retrospectively collected for all POMS cases treated with natalizumab in Portugal. RESULTS: Twenty-one patients were included, 14 (67%) of which were female. The median age at POMS diagnosis was 13 years old. The median duration of treatment with natalizumab was 2 years and 3 months. Median Expanded Disability Status Scale score decreased from 1.5 to 1.0 after 24 months. The Annualized Relapse Rate decreased from 1.31 events/patient/year before treatment with natalizumab to 0 after 12 months of treatment and to 0.04 after 24 months. No gadolinium-enhancing lesions or new or enlarged T2 hyperintense lesions were observed in 8/8 patients (100%) after 12 months, and 4/5 (80%) after 24 months. There was one possible serious adverse event, which did not require dose adjustment. Five patients discontinued treatment due to positive anti-JCV (JC virus) antibody JC serostatus. CONCLUSION: Natalizumab may be an effective and safe disease-modifying therapy for POMS. Our results are in line with data published for the adult population, as well as with similar observational studies in pediatric populations in other regions.

Stem Cell-Derived Neurons as Cellular Models of Sporadic Alzheimer's Disease.

Alzheimer's disease (AD) occurs as either an autosomal dominant inherited disease or sporadically. While familial mutant genes can be expressed in cells or in animal models to assess dysregulated functions, sporadic AD cannot be replicated in models given our lack of understanding of causality. Furthermore, the study of sporadic forms of AD is difficult given the inaccessibility of brain tissues in living individuals and the manifestation of symptoms years after the onset of disease. Here, the objective was to assess if induced pluripotent stem cell-derived neurons from well-ascertained sporadic AD individuals could represent potential cellular models to determine the underlying molecular mechanisms of disease. We used cryopreserved peripheral blood mononuclear cells from three well-ascertained sporadic AD and three non-cognitively impaired (NCI) individuals of the CIMA-Q cohort to obtain iPSC-derived neurons. Microtubule associated protein 2 was decreased in AD neurons, whereas expression of AD-associated amyloid precursor protein, tau, and amyloid-ß peptide was similar in AD and NCI individuals. RNA sequencing identified several upregulated and downregulated mRNAs in AD relative to NCI neurons. Of these, complement Factor H (CFH), signal regulatory protein beta1 (SIRPB1), and insulin like growth factor binding protein 5 (IGFBP5) were previously associated with AD. In addition, several transcription factors not previously associated with AD, but involved in neuronal proliferation and differentiation were differentially expressed. The results identify novel avenues for the study of the underlying causes of sporadic AD and support the establishment of additional lines to identify mechanisms of disease in sporadic AD individuals.

A sporadic case of late-onset familial amyloid polyneuropathy with a monoclonal gammopathy.

A 77-year-old Portuguese woman reported gradual worsening of burning and numbness in the feet and hands, fatigue, anorexia, weight loss, diarrhoea and decreased visual acuity. She had a medical history of atrial fibrillation and recent episodes of dizziness and blood pressure fluctuations. There was no relevant family history. The diagnostic workup documented a severe axonal sensorimotor peripheral neuropathy, a monoclonal IgG kappa protein on serum, a severe left ventricular hypertrophy on the echocardiogram and probable vitreous deposits of amyloid on ophthalmologic examination. Pain and dysautonomia with an axonal neuropathy and multisystemic involvement raised the possibility of amyloidosis. The presence of a detectable monoclonal protein, older age at disease onset and absence of family history of disease usually suggest immunoglobulin light-chain amyloidosis. However, in this case, both the genetic testing and the biopsy of the salivary glands confirmed transthyretin amyloidosis. In those patients with a monoclonal protein, particularly in sporadic and late-onset cases, the diagnosis of transthyretin amyloidosis can be challenging, mimicking immunoglobulin light-chain amyloidosis.

The usefulness of the head-up tilt test in patients with suspected epilepsy.

PURPOSE: It is estimated that approximately 20-30% of patients diagnosed with epilepsy have been misdiagnosed, and neurocardiogenic syncope (NCS) might frequently be the real cause of transient loss of consciousness (TLOC) episodes. We assessed the role of the head-up tilt test (HUTT) in patients previously diagnosed with refractory epilepsy to evaluate the ability of this test to correctly diagnose patients with NCS. METHOD: We retrospectively analysed the clinical records of 107 consecutive patients with a previous diagnosis of refractory epilepsy that were taking antiepileptic drugs and who were referred for HUTT between January 2000 and December 2010. During the subsequent follow-up, we recorded the treatments performed and the recurrence of symptoms. RESULTS: Complete follow-up data were available for 94 (88%) patients, and the mean follow-up period was 80±36 months. The HUTT was positive in 54% of patients. Thirty-one (33%) patients were misdiagnosed with epilepsy, and 20 (21%) patients had a dual diagnosis of NCS and epilepsy. The recurrence of TLOC was reported in 55% of the patients, but it was significantly lower in the misdiagnosed group (42% versus 64%; P=0.039). CONCLUSION: NCS is an important cause of epilepsy misdiagnosis. The HUTT is often critical for making an accurate diagnosis and subsequently selecting the appropriate treatment for patients presenting with TLOC. The diagnostic overlap between epilepsy and NCS is not uncommon, suggesting that electroencephalographic monitoring during a HUTT may play an important role in diagnosing patients with recurrent, undiagnosed TLOC episodes.

Selection of patients for percutaneous balloon mitral valvotomy: is there a definitive limit for the Wilkins score?

AIM: The aim of this study was to determine the early and long-term results of percutaneous balloon mitral valvotomy (PBMV) in patients with Wilkins score (WS) between 9 and 11. METHODS: We performed a retrospective review of clinical records of patients with rheumatic mitral stenosis who underwent PBMV between November 1991 and March 2008. Follow-up was obtained by telephone interview and/or clinical records. The procedure was considered unsuccessful when post-procedure mitral valve area was <1.5 cm(2). RESULTS: We analyzed 124 patients, 108 (87.1%) of them women. Mean age at the time of repair was 46 ± 11 years and mean follow-up time was 10 ± 4 years. Before the procedure, 100 patients (80.6%) had WS ≤ 8 and 24 (19.4%) were in the "gray zone" (>8 and <11). Patients with WS ≤ 8 and patients in the gray zone had similar ages at first intervention (45 ± 11 vs. 49 ± 11 years; p=0.095) and follow-up time (10 ± 4 vs. 11 ± 5 years; p=0.55). There were no differences between groups in gender (women: 86% vs. 92%; p=0.735), or in baseline echocardiographic measurements (mitral valve area by planimetry 1.0 cm(2) [P25-P75: 0.9-1.1] vs. 0.9 [P25-P75: 0.8-1.2], p=0.514; pulmonary artery systolic pressure 53 mmHg [P25-P75: 45-63] vs. 50 [P25-P75: 44-54], p=0.823]; left atrial diameter >55 mm [16.5% vs. 13.6%, p=1.00]; mitral regurgitation [46.5% vs. 37.5%, p=0.428]) or baseline transmitral gradient (13 mmHg [P25-P75: 10-19] vs. 13 mmHg [P25-P75: 7-20]). Improvements in mitral valve area by planimetry and in hemodynamic gradient were similar in the two groups (0.91 ± 0.39 cm(2) vs. 0.84 ± 0.44 cm(2), p=0.55; 8.8 ± 5.3 mmHg vs. 7.3 ± 5.9 mmHg, p=0.275, respectively). There were no significant differences in major complications or success rates (4.0 vs. 12.5 p=0.131; 89.9% vs. 95.8%, p=0.69) or in need for urgent surgery or future reintervention (2.0 vs. 8.3%, p=0.168; 22% vs. 27.3%, p=0.594). In-hospital mortality occurred only in patients in the WS gray zone (2 [8.3%] vs. 0%, p=0.04), one death (4.2% vs. 0%, p=0.194) possibly being related to a higher WS (secondary to stroke) and the other as a consequence of peripheral vascular complication. Improvements in NYHA functional class soon after the procedure and during follow-up were similar in the two groups. Total mortality was similar in the two groups (3.1 vs. 8.7%, p=0.244). CONCLUSIONS: PBMV was a safe and effective procedure in patients in the WS gray zone. Optimal results can be achieved in these patients if they are carefully selected and operated at experienced centers.

Long-term follow-up after aortic coarctation repair: the unsolved issue of exercise-induced hypertension.

INTRODUCTION: Despite successful repair of aortic coarctation (AC), systemic hypertension (HTN) can persist in a significant percentage of patients. Exercise-induced HTN is also common in these patients, although its clinical significance is still unclear. In this study we aimed to assess the prevalence of exercise-induced HTN in adult patients with repaired AC. METHODS: We retrospectively reviewed the clinical records of patients aged >18 years with repaired AC followed at an adult congenital heart disease outpatient clinic in a tertiary care center. Demographic and clinical data including age at intervention, blood pressure (BP) at rest and on exercise, transthoracic echocardiogram (TTE) and treadmill exercise test results were evaluated. Exercise-induced HTN was defined as peak systolic BP ≥ 210 mmHg for men and ≥ 190 mmHg for women. RESULTS: We analyzed 65 patients (40 [61.5%] male; mean age at follow-up 30 ± 8 years). Median age at AC repair was 7 years (P25-P75: 4-20) and mean follow-up was 20 ± 7 years. Only one patient had diabetes and 10 (15.4%) had dyslipidemia. The majority of patients had controlled BP at rest and only nine (18%) were under antihypertensive medication. Forty-nine patients performed a treadmill exercise test. The mean duration of exercise was 10.7 ± 3.1 minutes and mean peak heart rate was 166 ± 18 beats per minute. Eleven (22%) patients had a hypertensive response, among whom only three (33%) had uncontrolled BP at rest. In our study treatment with angiotensin-converting enzyme inhibitors (ACEI) (OR 4.0 [95% CI 1.9-18.1]) and the peak instantaneous gradient in the descending aorta by TTE (OR 8.2 [95% CI 1.8-37.0]) were predictors of a hypertensive response with exercise. Age at surgery and type of AC repair were not associated with a hypertensive response on exercise. CONCLUSIONS: In this study we found a significant prevalence of exercise-induced HTN in adult patients after successful AC repair despite adequate BP control at rest. Exercise-induced HTN was significantly related to higher peak gradient in the descending aorta and treatment with ACEI. These results highlight the complexity of the adult AC population and show that, even after a good surgical result, several patients remain at high cardiovascular risk and require long-term follow-up.

Churg-Strauss syndrome presenting with eosinophilic myocarditis: a diagnostic challenge.

Churg-Strauss syndrome (CSS) is an unusual disease that presents as systemic vasculitis and peripheral eosinophilia in patients with an atopic constitution. Cardiac involvement is unusual and often not prominent on initial presentation, but is an important cause of morbidity and mortality in patients with CSS. We report the case of a young woman with severe acute myocarditis. Coronary arteriography demonstrated extensive focal vasculopathy, consistent with coronary vasculitis, and myocardial biopsy showed eosinophilic myocarditis. This presentation led to an initial diagnosis of CSS in this patient and appropriate therapy resulted in a spectacular remission of disease activity.

Long-term survival, autonomy, and quality of life of elderly patients undergoing aortic valve replacement.

AIMS: We reviewed the long-term survival, autonomy, and quality of life (QoL) of elderly patients undergoing aortic valve replacement (AVR). METHODS: Records of patients ≥75 years old that underwent AVR from 2002 to 2006 were retrospectively analyzed. Functional status was classified with Barthel Index (BI). QoL was presumed as the self-perception of well-being after AVR. Independent predictors of mortality were identified using the Cox proportional hazards model. RESULTS: We included 114 patients, with a mean age of 78.5 ± 2.5 years. Seventy (59.8%) patients were females. Mean additive and logistic EuroSCORE were 7 ± 2 and 9 ± 7, respectively. Follow-up on vital status was achieved for 113 (99.1%) patients after a mean period of 47.2 ± 23.4 months. Twenty-seven (23.7%) patients died (including three operative deaths). Survival up to one, three, and five years of follow-up was 94.4%, 86.7%, and 76.1%, respectively. Multivariate analysis showed that pulmonary hypertension and diabetes were independent predictors of all-cause mortality. Information on BI score and QoL was obtained for 77 (89.5%) and patients. Among those, 69 (89.6%) were autonomous according to BI and 72 (93.5%) considered having had an improvement in QoL. CONCLUSION: Patients ≥75 years old undergoing AVR presented good medium-term survival. Predictors of an adverse outcome were significant pulmonary hypertension and diabetes. At follow-up, most achieved improvement of QoL and remained autonomous. These results stress that excellent long-term outcomes with AVR can be achieved in appropriately selected elderly patients.

Inhibition of notch signaling in glioblastoma targets cancer stem cells via an endothelial cell intermediate.

Glioblastoma multiforme (GBM) is a highly heterogeneous malignant tumor. Recent data suggests the presence of a hierarchical organization within the GBM cell population that involves cancer cells with stem-like behavior, capable of repopulating the tumor and contributing to its resistance to therapy. Tumor stem cells are thought to reside within a vascular niche that provides structural and functional support. However, most GBM studies involve isolated tumor cells grown under various culture conditions. Here, we use a novel three-dimensional organotypic "explant" system of surgical GBM specimens that preserves cytoarchitecture and tumor stroma along with tumor cells. Notch inhibition in explants results in decreased proliferation and self-renewal of tumor cells but is also associated with a decrease in endothelial cells. When endothelial cells are selectively eliminated from the explants via a toxin conjugate, we also observed a decrease in self-renewal of tumor stem cells. These findings support a critical role for tumor endothelial cells in GBM stem cell maintenance, mediated at least in part by Notch signaling. The explant system further highlighted differences in the response to radiation between explants and isolated tumor neurospheres. Combination treatment with Notch blockade and radiation resulted in a substantial decrease in proliferation and in self-renewal in tumor explants while radiation alone was less effective. This data suggests that the Notch pathway plays a critical role in linking angiogenesis and cancer stem cell self-renewal and is thus a potential therapeutic target. Three-dimensional explant systems provide a novel approach for the study of tumor and microenvironment interactions.

Growth factors and feeder cells promote differentiation of human embryonic stem cells into dopaminergic neurons: a novel role for fibroblast growth factor-20.

Human embryonic stem cells (hESCs) are a potential source of dopaminergic neurons for treatment of patients with Parkinson's disease (PD). Dopaminergic neurons can be derived from hESCs and display a characteristic midbrain phenotype. Once transplanted, they can induce partial behavioral recovery in animal models of PD. However, the potential research field faces several challenges that need to be overcome before clinical application of hESCs in a transplantation therapy in PD can be considered. These include low survival of the hESC-derived, grafted dopaminergic neurons after transplantation; unclear functional integration of the grafted neurons in the host brain; and, the risk of teratoma/tumor formation from the transplanted cells. This review is focused on our recent efforts to improve the survival of hESC-dervied dopaminergic neurons. In a recent study, we examined the effect of fibroblast growth factor (FGF)-20 in the differentiation of hESCs into dopaminergic neurons. We supplemented cultures of hESCs with FGF-20 during differentiation on PA6 mouse stromal cells for 3 weeks. When we added FGF-20 the yield of neurons expressing tyrosine hydroxylase increased. We demonstrated that at least part of the effect is contributed by enhanced cell differentiation towards the dopaminergic phenotype as well as reduced cell death. We compare our results with those obtained in other published protocols using different sets of growth factors. Taken together, our data indicate that FGF-20 has potent effects to generate large number of dopaminergic neurons derived from hESCs, which may be useful for hESC-based therapy in PD.

Transplantation of human embryonic stem cell-derived cells to a rat model of Parkinson's disease: effect of in vitro differentiation on graft survival and teratoma formation.

Human embryonic stem cells (hESCs) have been proposed as a source of dopamine (DA) neurons for transplantation in Parkinson's disease (PD). We have investigated the effect of in vitro predifferentiation on in vivo survival and differentiation of hESCs implanted into the 6-OHDA (6-hydroxydopamine)-lesion rat model of PD. The hESCs were cocultured with PA6 cells for 16, 20, or 23 days, leading to the in vitro differentiation into DA neurons. Grafted hESC-derived cells survived well and expressed neuronal markers. However, very few exhibited a DA neuron phenotype. Reversal of lesion-induced motor deficits was not observed. Rats grafted with hESCs predifferentiated in vitro for 16 days developed severe teratomas, whereas most rats grafted with hESCs predifferentiated for 20 and 23 days remained healthy until the end of the experiment. This indicates that prolonged in vitro differentiation of hESCs is essential for preventing formation of teratomas.

Stem cell-based therapy for Parkinson's disease.

Motor dysfunctions in Parkinson's disease are considered to be primarily due to the degeneration of dopaminergic neurons in the substantia nigra pars compacta. Pharmacological therapies based on the principle of dopamine replacement are extremely valuable, but suffer from two main drawbacks: troubling side effects (e.g. dyskinesia) and loss of efficacy with disease progression. Transplantation of embryonic dopaminergic neurons has emerged as a therapeutic alternative. Enthusiasm following the success of the initial open-label trials has been dampened by the negative outcome of double-blind placebo controlled trials. Additionally, the emergence of graft-related dyskinesia indicates that the experimental grafting procedure requires further refinement before it can be developed into a therapy. Shortage of embryonic donor tissue limits large-scale clinical transplantation trials. We review three of the most attractive tissue sources of dopaminergic neurons for cell replacement therapy: human embryonic ventral mesencephalic tissue, embryonic and adult multipotent region-specific stem cells and embryonic stem cells. Recent developments in embryonic stem cell research and on their implications for a future transplantation therapy in Parkinson's disease are described. Finally, we discuss how human embryonic stem cells can be differentiated into dopaminergic neurons, and issues such as the numbers of dopaminergic neurons required for success and the risk for teratoma formation after implantation.