Rufinamide in children and adults in routine clinical practice

OBJECTIVE

To explore the long-term effectiveness of rufinamide in managing Lennox-Gastaut Syndrome (LGS), other epileptic encephalopathies, and intractable focal epilepsies in adults and children in routine clinical practice.

METHODS

A multicentre, retrospective chart review of patients prescribed adjunctive rufinamide at seven Spanish epilepsy centres, with assessments at six and 12 months.

RESULTS

We evaluated data from 58 patients (40 male, age range 7-57 years), 25 of whom were diagnosed with LGS, 12 with other epileptic encephalopathies and 21 of whom were diagnosed with focal epilepsies, mainly frontal lobe. The mean daily rufinamide dose was 32.0 mg/kg (range 12.5-66.7 mg/kg) in children and 24.7 mg/kg (range 5.0-47.0 mg/kg) in adults, and the most commonly used concomitant antiepileptic drugs were levetiracetam and valproate. Rufinamide was discontinued in 25 patients (43.1%) during the 1-year follow-up, and the most common reason was lack of effectiveness (n = 12, 20.7% of total). The frequency of generalized tonic-clonic seizures was significantly reduced from baseline at 6 and 12 months (P = 0.001), both in patients with generalized epilepsies and in patients with focal epilepsies. Significant seizure frequency reduction from baseline was observed at 12 months (P = 0.01) for tonic/atonic seizures and at 6 months (P = 0.001) for focal seizures. Side effects were reported in 21 patients (36.2%): nausea, vomiting and weight loss were most frequent.

CONCLUSIONS

Rufinamide was well tolerated and was effective in reducing frequency of generalized tonic-clonic, tonic/atonic and focal seizures in both children and adults with severe refractory epilepsies, primarily LGS.

Expression of insulin receptor (IR) A and B isoforms, IGF-IR, and IR/IGF-IR hybrid receptors in vascular smooth muscle cells and their role in cell migration in atherosclerosis

Background

Abnormal proliferation and migration of vascular smooth muscle cells (VSMCs) is a major contributor to the development of atherosclerotic process. In a previous work, we demonstrated that the insulin receptor isoform A (IRA) and its association with the insulin-like growth factor-I receptor (IGF-IR) confer a proliferative advantage to VSMCs. However, the role of IR and IGF-IR in VSMC migration remains poorly understood.

Methods

Wound healing assays were performed in VSMCs bearing IR (IRLoxP^+/+ VSMCs), or not (IR^−/− VSMCs), expressing IRA (IRA VSMCs) or expressing IRB (IRB VSMCs). To study the role of IR isoforms and IGF-IR in experimental atherosclerosis, we used ApoE^−/− mice at 8, 12, 18 and 24 weeks of age. Finally, we analyzed the mRNA expression of total IR, IRB isoform, IGF-IR and IGFs by qRT-PCR in the medial layer of human aortas.

Results

IGF-I strongly induced migration of the four cell lines through IGF-IR. In contrast, insulin and IGF-II only caused a significant increase of IRA VSMC migration which might be favored by the formation of IRA/IGF-IR receptors. Additionally, a specific IGF-IR inhibitor, picropodophyllin, completely abolished insulin- and IGF-II-induced migration in IRB, but not in IRA VSMCs. A significant increase of IRA and IGF-IR, and VSMC migration were observed in fibrous plaques from 24-week-old ApoE^−/− mice. Finally, we observed a marked increase of IGF-IR, IGF-I and IGF-II in media from fatty streaks as compared with both healthy aortas and fibrolipidic lesions, favoring the ability of medial VSMCs to migrate into the intima.

Conclusions

Our data suggest that overexpression of IGF-IR or IRA isoform, as homodimers or as part of IRA/IGF-IR hybrid receptors, confers a stronger migratory capability to VSMCs as might occur in early stages of atherosclerotic process.

Electronic supplementary material

The online version of this article (doi:10.1186/s12933-016-0477-3) contains supplementary material, which is available to authorized users.

Severe Brown Fat Lipoatrophy Aggravates Atherosclerotic Process in Male Mice

Obesity is one of the major risk factors for the development of cardiovascular diseases and is characterized by abnormal accumulation of adipose tissue, including perivascular adipose tissue (PVAT). However, brown adipose tissue (BAT) activation reduces visceral adiposity. To demonstrate that severe brown fat lipoatrophy might accelerate atherosclerotic process, we generated a new mouse model without insulin receptor (IR) in BAT and without apolipoprotein (Apo)E (BAT-specific IR knockout [BATIRKO];ApoE(-/-) mice) and assessed vascular and metabolic alterations associated to obesity. In addition, we analyzed the contribution of the adipose organ to vascular inflammation. Brown fat lipoatrophy induces visceral adiposity, mainly in gonadal depot (gonadal white adipose tissue [gWAT]), severe glucose intolerance, high postprandial glucose levels, and a severe defect in acute insulin secretion. BATIRKO;ApoE(-/-) mice showed greater hypertriglyceridemia than the obtained in ApoE(-/-) and hypercholesterolemia similar to ApoE(-/-) mice. BATIRKO;ApoE(-/-) mice, in addition to primary insulin resistance in BAT, also showed a significant decrease in insulin signaling in liver, gWAT, heart, aorta artery, and thoracic PVAT. More importantly, our results suggest that severe brown fat lipoatrophy aggravates the atherosclerotic process, characterized by a significant increase of lipid depots, atherosclerotic coverage, lesion size and complexity, increased macrophage infiltration, and proinflammatory markers expression. Finally, an increase of TNF-α and leptin as well as a decrease of adiponectin by BAT, gWAT, and thoracic PVAT might also be responsible of vascular damage. Our results suggest that severe brown lipoatrophy aggravates atherosclerotic process. Thus, BAT activation might protect against obesity and its associated metabolic alterations.

Insulin receptor isoform A ameliorates long-term glucose intolerance in diabetic mice

Type 2 diabetes mellitus is a complex metabolic disease and its pathogenesis involves abnormalities in both peripheral insulin action and insulin secretion. Previous in vitro data showed that insulin receptor isoform A, but not B, favours basal glucose uptake through its specific association with endogenous GLUT1/2 in murine hepatocytes and beta cells. With this background, we hypothesized that hepatic expression of insulin receptor isoform A in a mouse model of type 2 diabetes could potentially increase the glucose uptake of these cells, decreasing the hyperglycaemia and therefore ameliorating the diabetic phenotype. To assure this hypothesis, we have developed recombinant adeno-associated viral vectors expressing insulin receptor isoform A (IRA) or isoform B (IRB) under the control of a hepatocyte­-specific promoter. Our results demonstrate that in the long term, hepatic expression of IRA in diabetic mice is more efficient than IRB in ameliorating glucose intolerance. Consequently, it impairs the induction of compensatory mechanisms through beta cell hyperplasia and/or hypertrophy that finally lead to beta cell failure, reverting the diabetic phenotype in about 8 weeks. Our data suggest that long-term hepatic expression of IRA could be a promising therapeutic approach for the treatment of type 2 diabetes mellitus.

Summary: The specific hepatic expression of insulin receptor isoform A, but not isoform B, is able to revert, in the long term, the global glucose intolerance observed in diabetic mice.

Essential Role of IGFIR in the Onset of Male Brown Fat Thermogenic Function: Regulation of Glucose Homeostasis by Differential Organ-Specific Insulin Sensitivity

Brown fat is a thermogenic tissue that generates heat to maintain body temperature in cold environments and dissipate excess energy in response to overfeeding. We have addressed the role of the IGFIR in the brown fat development and function. Mice lacking IGFIR exhibited normal brown adipose tissue/body weight in knockout (KO) vs control mice. However, lack of IGFIR decreased uncoupling protein 1 expression in interscapular brown fat and beige cells in inguinal fat. More importantly, the lack of IGFIR resulted in an impaired cold acclimation. No differences in the total fat volume were found in the KO vs control mice. Epididymal fat showed larger adipocytes but with a lower number of adipocytes in KO vs control mice at age 12 months. In addition, KO mice showed a sustained moderate hyperinsulinemia and hypertriglyceridemia upon time and hepatic insulin insensitivity associated with lipid accumulation, with the outcome of a global insulin resistance. In addition, we found that the expression of uncoupling protein 3 in the skeletal muscle was decreased and its expression was increased in the heart in parallel with the expression of beta-2 adrenergic receptors. Upon nonobesogenic high-fat diet, we found a severe insulin resistance in the liver and in the skeletal muscle, but unchanged insulin sensitivity in the heart. In conclusion, our data suggest that IGFIR it is not an essential growth factor in the brown fat development in the presence of the IR and very high plasma levels of IGF-I, but it is indispensable for full brown fat functionality.

Astrocyte Resilience to Oxidative Stress Induced by Insulin-like Growth Factor I (IGF-I) Involves Preserved AKT (Protein Kinase B) Activity

Disruption of insulin-like growth factor I (IGF-I) signaling is a key step in the development of cancer or neurodegeneration. For example, interference of the prosurvival IGF-I/AKT/FOXO3 pathway by redox activation of the stress kinases p38 and JNK is instrumental in neuronal death by oxidative stress. However, in astrocytes, IGF-I retains its protective action against oxidative stress. The molecular mechanisms underlying this cell-specific protection remain obscure but may be relevant to unveil new ways to combat IGF-I/insulin resistance. Here, we describe that, in astrocytes exposed to oxidative stress by hydrogen peroxide (H2O2), p38 activation did not inhibit AKT (protein kinase B) activation by IGF-I, which is in contrast to our previous observations in neurons. Rather, stimulation of AKT by IGF-I was significantly higher and more sustained in astrocytes than in neurons either under normal or oxidative conditions. This may be explained by phosphorylation of the phosphatase PTEN at the plasma membrane in response to IGF-I, inducing its cytosolic translocation and preserving in this way AKT activity. Stimulation of AKT by IGF-I, mimicked also by a constitutively active AKT mutant, reduced oxidative stress levels and cell death in H2O2-exposed astrocytes, boosting their neuroprotective action in co-cultured neurons. These results indicate that armoring of AKT activation by IGF-I is crucial to preserve its cytoprotective effect in astrocytes and may form part of the brain defense mechanism against oxidative stress injury.

Clinical, virological and phylogenetic characterization of a multiresistant HIV-1 strain outbreak in naive patients in southern Spain

BACKGROUND

We describe the characteristics of an HIV-1 strain with six viral reverse transcriptase mutations (D67N, T69N/D, V118I, V179D, T215S and K219Q), which we have called the Malaga strain. This strain was detected in treatment-naive patients from southern Spain.

METHODS

The study was undertaken at the Virgen de la Victoria Hospital, Malaga, a reference centre for the study of HIV-1 genotype resistance in Andalusia (the 'Costa del Sol'), Spain. Genotypic resistance testing was done in an automated sequencer. Phylogenetic analysis was performed using a 630 bp region of the reverse transcriptase with the mutations mentioned.

RESULTS

Between 2007 and 2014, we detected the Malaga strain in 30 treatment-naive patients. All were MSM, seen at five hospitals on the Costa del Sol. In all cases, the HIV-1 was subtype B with viral tropism R5. Phylogenetic analysis based on the reverse transcriptase sequence showed consistent grouping (with a bootstrap value of the common node of 100%) of the isolates that shared the mutation pattern mentioned. This strain has not been detected elsewhere or in previously treated patients. All of the patients treated with first-line combination ART responded.

CONCLUSIONS

We report a cluster of an HIV-1 strain with multiple resistance mutations that was transmitted over a period of >8 years, affecting 30 naive patients from the same geographical area. The strain was susceptible to first-line combination ART.

Sialadenitis after radioiodine therapy. Analysis of factors that influence the response to medical treatment

OBJECTIVES

To assess the incidence of 131I-induced sialadenitis (SD) in patients with differentiated thyroid cancer (DTC), to analyze clinical and other factors related to metabolic radiotherapy that may predict the lack of response to conventional medical therapy (CMT), and to determine the effectiveness of intraductal steroid instillation in patients failing CMT.

MATERIAL AND METHODS

Fifty-two patients with DTC, 45 females (86.5%) and 7 males (13.5%) with a mean age of 44.21±13.3 years (r=17-74) who received ablation therapy with 131I after total thyroidectomy. Patients with diseases and/or medication causing xerostomia were excluded. Patients underwent salivary gland scintigraphy with 99Tc (10mCi).

RESULTS

Eighteen patients (34.62%) had SD and received antibiotics, antispasmodics, and oral steroids for 15 days. They were divided into two groups: responders to medical therapy (n=12, age 44.3±14.4 years, 2 men [17%], 10 women [83%], cumulative dose 225±167.1 mCi) and non-responders to medical treatment, who underwent steroid instillation into the Stensen's duct (n=6 [33%], 2 men [33%], 4 women [67%], age 50±13.8 years, cumulative dose 138.3±61.7 mCi). Scintigraphy showed damage to the parotid and submaxillary glands.

CONCLUSION

Incidence of 131I-induced sialadenitis was similar to that reported by other authors. Age, mean cumulative dose of 131I, and involvement of parotid and submaxillary glands did not condition response to CMT; however, male sex was a conditioning factor. Symptom persistence for more than 15 days makes instillation into the Stensen's duct advisable. This is an effective and safe method to avoid surgical excision of salivary glands.

Small-vessel vasculitis with prominent IgG4 positive plasma cell infiltrates as potential part of the spectrum of IgG4-related disease: a case report

IgG4-related disease (IgG4-RD) is a systemic entity characterised by multiorgan inflammatory lesions with abundant IgG4+ plasma cells, obliterative phlebitis, and storiform fibrosis. Involvement of several organs such as the pancreas, gastrointestinal tract, salivary glands, periorbital tissue and lymph nodes has been described. Up to now, vascular involvement by IgG4-RD has been thought to be essentially confined to large vessels. We present a patient with small-vessel systemic vasculitis involving muscle, peripheral nerve and kidney (glomerulonephritis) in the context of IgG4-RD diagnosed on the basis of elevated serum IgG4+ concentrations and histologically consistent signs in all biopsied tissues. Thoracic and abdominal aortic aneurysms in addition to aortitis, suggestive of large-vessel involvement, were also present. This observation expands the spectrum of vascular involvement in the context of IgG4-RD and supports the inclusion of IgG4-RD in the category of vasculitis associated with systemic disorder.

PET/MRI and PET/MRI/SISCOM coregistration in the presurgical evaluation of refractory focal epilepsy

We aimed to investigate the usefulness of coregistration of positron emission tomography (PET) and magnetic resonance imaging (MRI) findings (PET/MRI) and of coregistration of PET/MRI with subtraction ictal single-photon emission computed tomography (SPECT) coregistered to MRI (SISCOM) (PET/MRI/SISCOM) in localizing the potential epileptogenic zone in patients with drug-resistant epilepsy. We prospectively included 35 consecutive patients with refractory focal epilepsy whose presurgical evaluation included a PET study. Separately acquired PET and structural MRI images were coregistered for each patient. When possible, ictal SPECT and SISCOM were obtained and coregistered with PET/MRI. The potential location of the epileptogenic zone determined by neuroimaging was compared with the seizure onset zone determined by long-term video-EEG monitoring and with invasive EEG studies in patients who were implanted. Structural MRI showed no lesions in 15 patients. In these patients, PET/MRI coregistration showed a hypometabolic area in 12 (80%) patients that was concordant with seizure onset zone on EEG in 9. In 7 patients without MRI lesions, PET/MRI detected a hypometabolism that was undetected on PET alone. SISCOM, obtained in 25 patients, showed an area of hyperperfusion concordant with the seizure onset zone on EEG in 7 (58%) of the 12 of these patients who had normal MRI findings. SISCOM hyperperfusion was less extensive than PET hypometabolism. A total of 19 patients underwent surgery; 11 of these underwent invasive-EEG monitoring and the seizure onset zone was concordant with PET/MRI in all cases. PET/MRI/SISCOM coregistration, performed in 4 of these patients, was concordant in 3 (75%). After epilepsy surgery, 13 (68%) patients are seizure-free after a mean follow-up of 4.5 years. PET/MRI and PET/MRI/SISCOM coregistration are useful for determining the potential epileptogenic zone and thus for planning invasive EEG studies and surgery more precisely, especially in patients without lesions on MRI.