Analysis of humoral and cellular immunity after SARS-CoV-2 vaccination in patients with multiple sclerosis treated with immunomodulatory drugs.

We analyzed immune response to SARS-CoV-2 vaccination by measuring specific IgG titers and T-cell reactivity to different SARS-CoV-2 peptides in multiple sclerosis patients taking different disease-modifying treatments. Of the 88 patients included, 72 developed any kind of immune response after vaccination. Although DMTs such as fingolimod and anti-CD20+ treatments prevented patients from developing a robust humoral response to the vaccine, most of them were still able to develop a cellular response, which could be crucial for long-term immunity. It is probably advisable that all MS patients take additional/booster doses to increase their humoral and/or cellular immune response to SARS-CoV-2.

Extensive pharmacokinetic variability of Levetiracetam. ¿Are doctors aware?

INTRODUCTION: Levetiracetam was presented as a drug with linear pharmacokinetics. There is currently evidence on its extensive pharmacokinetic variability in real clinical practice. OBJECTIVE: To describe levetiracetam pharmacokinetic variability in patients with epilepsy in real clinical practice. To evaluate the effect on levetiracetam levels of gender, age, renal function, and polytherapy. To describe how clinicians prescribe based on age and co-medication. METHODS: Retrospective analysis of epilepsy patients treated with levetiracetam for whom plasma levels were available. RESULTS: 151 patients. Median levetiracetam level of 17.75 mg/L, median dose of 2000 mg/day. There was a significant correlation between daily dose and serum levels (p < 0.01). There was a 18.1% increase in levetiracetam concentration/dose ratio in patients over 65 years of age (p < 0.05) that also correlated with decreased glomerular filtration (p < 0.01). Clinicians corrected doses so patients over 65 years had similar levels than younger patients. There was a 30.1% decrease of concentration/dose ratio in patients on polytherapy with potent enzyme inducer antiseizure medication (p < 0.05), and a 46.3% decrease for carbamazepine (p < 0.01). Clinicians did not correct doses, so patients treated with levetiracetam and carbamazepine had 27.5% lower levels than patients taking other polytherapy. CONCLUSION: The pharmacokinetic variability of levetiracetam is wider than originally thought. Age and co-medication with strong enzyme-inducing drugs, especially carbamazepine, significantly influence levetiracetam levels. Clinicians at our center did not consider this interaction and prescribed similar doses of levetiracetam when it was used in combination with these drugs or with others, so they probably were not aware of this interaction.

Detection of hidden atrial fibrillation in primary care using a long-term band-based ECG registration system: The DESCUUBRE-FA study.

OBJECTIVE: To assess whether the use of a band-based electrocardiographic (ECG) monitoring system improves the diagnostic accuracy of traditional diagnostic methods for the detection of atrial fibrillation (AF). METHODS: Multicenter and observational study of primary care patients at risk of AF. To be included, patients had to be aged ≥70 years, with no known AF, and have at least 1 major criterion (obesity, hyperthyroidism, heart failure) or 2 minor criteria (hypertension, diabetes, female sex, ischemic stroke, transient ischemic attack or systemic embolism, COPD, dyslipidemia, ischemic heart disease, peripheral artery disease). All patients were monitored using the Nuubo™ system for a single 2-week period. RESULTS: A total of 600 patients were included (median age 77 years; 70% women; 84.3% hypertension, 27.2% diabetes, 9.2% prior stroke). The global rate of diagnosis of new AF in the overall population was 2.83%. All patients with AF were anticoagulated. In numerical terms, patients with AF (vs no AF) had a higher number of supraventricular extrasystoles and episodes of supraventricular tachycardia, as well as longer P wave duration; however, these differences did not reach statistical significance. Overall, participants were very satisfied with the device, and no relevant limitations in daily activities were observed during the 2-week study period. CONCLUSIONS: In an elderly population at risk of AF, a band-based ECG monitoring approach applied for only 2 weeks detected approximately 3% of new cases of AF, leading to a change in antithrombotic therapy. Most participants considered the device easy to use and comfortable.

Pharmacokinetic variability of eslicarbazepine in real clinical practice.

INTRODUCTION: Eslicarbazepine acetate (ESL) is a sodium channel blocker indicated for partial-onset seizures with or without secondary generalization, at a single daily dose. There are very few publications on the levels of ESL metabolites in real clinical practice. OBJECTIVE: To describe the serum levels of licarbazepine (main metabolite of ESL) in patients with refractory epilepsy in real clinical practice. To evaluate the influence of age, sex, and polytherapy on levels and adverse effects. METHODS: This study involved a retrospective analysis of patients diagnosed with epilepsy treated with ESL for whom plasma levels of licarbazepine were available, measured by spectrophotometry. RESULTS: Sixty-four patients were included. One patient had licarbazepine levels of 0 (admitted not taking the drug) was not analyzed. Mean licarbazepine levels of 7.66 µg/mL (400 mg/day dose), 16.56 µg/mL (800-mg dose), and 20.80 µg/mL (1200 mg) were significantly different. There was a significant correlation between daily dose and serum levels (p < 0.05) and between the concentration/dose ratio and lower to higher doses (p < 0.05). Pharmacokinetic variability (coefficient of variation for the concentration/dose ratio) was 33.2%. We found a decrease in the concentration/dose ratio in the 1200 mg/day dose, compared to lower doses. We did not find differences by sex or intake of other antiepileptic inducers or metabolic inhibitors. Fifteen patients (23.8%) had mild nonsymptomatic hyponatremia. CONCLUSION: These results suggest that it is not necessary to routinely determine licarbazepine levels. In specific cases, licarbazepine levels can be useful to assess adherence to treatment and for personalized dose adjustment.

Time Trends in Intracerebral Hemorrhage Associated with Oral Anticoagulation and Its Risks Factors in Spain from 2008 to 2015.

BACKGROUND: Intracerebral hemorrhage (ICH) is 7- to 10-fold higher in anticoagulated patients. Given the more extended use of oral anticoagulants, an increase in the prevalence of ICH associated with oral anticoagulation (ICH-OAC) could be expected. However, there is no previous study that assesses the time trends of ICH-OAC in Spain. METHODS: We conducted a combined data analysis after creating a joint database of the 3 most important epidemiological studies on ICH-OAC of our country: the EPICES study (2008-2009), the TAC Registry (TR) study (2012-2013) and the TAC Registry 2 (TR2) study (2015). We finally included 65, 235, and 366 patients from the EPICES, TR, and TR2 studies, respectively. RESULTS: We have observed a 3.73-fold increase in the crude annual incidence of ICH-OAC throughout the period of study, with proportion of ICH-OAC out of total ICH increasing from 8.4% in 2008 to 18.2% in 2015. Age, dyslipidemia, and prior antiplatelet treatment increased during the study, but we found no statistically significant differences in other risk factors for ICH-OAC. CONCLUSIONS: The incidence of ICH-OAC is increasing in our country. It might at least be partly explained by aging of the population, with mean age at presentation being higher in the last years.

[Gender inequalities in the impacts of informal elderly caregiving in Gipuzkoa: CUIDAR-SE study]. / Desigualdades de género en los impactos del cuidado informal de mayores dependientes en Gipuzkoa: Estudio CUIDAR-SE.

OBJECTIVE: The provision of informal care determines the existence of health inequalities, as well as gender inequalities, because of women being the most frequent caregivers. The objectives of this study were to characterize the informal caregivers of elderly dependents in Gipuzkoa, to know the impact of caring on health and health related quality of life (HRQoL), and to explain the relationship between sex and consequences attributable to care. METHODS: Cross-sectional study analyzing health (self-perceived health and GHQ-12) and HRQoL (EQ-5D-5L) data of 123 women and 103 men who took care of a dependent elderly and participated in the first wave of the CUIDAR-SE study in Gipuzkoa. A descriptive study was performed, and a logistic regression analysis was carried out to examine the association between sex and the consequences attributable to care. RESULTS: Women and men were over 60 years old, married, with primary education or less, and took care of their parents mainly. Women presented worse perceived health (46.3% vs 32.0%) and mental health (23.3% vs 13.9%), and more problems in the dimensions of anxiety/depression (35.0% vs 21.4%) and pain/discomfort (52.8% vs 31.1%) of EQ-5D-5L.The regression model showed greater risk of fatigue (OR = 2.83; 95% CI:1.53-5.24) and burden (OR = 1.87; 95% CI: 1.06-3.29) among women than among men. CONCLUSIONS: There are gender inequalities in the provision of informal care to dependent elderly people in Gipuzkoa, with women having a greater impact on their health and HRQoL than men. Considering the organization of care in this province, it will be necessary to design improvement actions more suited to the needs of caregivers.

OBJETIVO: La prestación de cuidados informales determina la existencia de desigualdades en salud, a las cuales se suman las desigualdades de género por el papel mayoritario de las mujeres en dicha prestación. Los objetivos de este estudio fueron caracterizar a la población cuidadora informal de mayores dependientes en Gipuzkoa, conocer los impactos de cuidar sobre la salud y la calidad de vida relacionada con la salud (CVRS), y explicar la relación entre el sexo y las consecuencias atribuibles al cuidado. METODOS: Estudio transversal en el que se analizaron datos de salud (salud percibida y GHQ-12) y CVRS (EQ-5D-5L) de 123 mujeres y 103 hombres cuidadores de mayores dependientes que participaron en la primera oleada del estudio CUIDAR-SE en Gipuzkoa. Se realizó un estudio descriptivo, y un análisis de regresión logística para examinar la asociación entre el sexo y las consecuencias del cuidado. RESULTADOS: Mujeres y hombres tenían más de 60 años, estaban casadas/os, tenían educación primaria o inferior, y cuidaban a sus progenitores fundamentalmente. Las mujeres presentaban peor salud percibida (46,3% vs 32,0%) y mental (23,3% vs 13,9%), y más problemas en las dimensiones de ansiedad/depresión (35,0% vs 21,4%) y dolor/malestar (52,8% vs 31,1%) de laEQ-5D-5L. El modelo de regresión mostró mayor riesgo de cansancio (OR=2,83; IC95%:1,53-5,24) y sobrecarga (OR=1,87; IC95%:1,06-3,29) en mujeres que en hombres. CONCLUSIONES: Existen desigualdades de género en la provisión de cuidados informales a mayores dependientes en Gipuzkoa, mostrando las mujeres un mayor impacto en su salud y CVRS que los hombres. Considerando la organización del cuidado en esta provincia, será necesario el diseño de acciones de mejora más adecuadas a las necesidades de las personas cuidadoras.

To what extent are patients with migraine able to predict attacks?

PURPOSE: Premonitory symptoms (PSs) of migraine are those that precede pain in a migraine attack. Previous studies suggest that treatment during this phase may prevent the onset of pain; however, this approach requires that patients be able to recognize their PSs. Our objectives were to evaluate patients' actual ability to predict migraine attacks based on their PSs and analyze whether good predictors meet any characteristic profile. PATIENTS AND METHODS: This prospective, observational study included patients with migraine with and without aura. Patients' baseline characteristics were recorded. During a 2-month follow-up period, patients used a mobile application to record what they believed to be PSs and later to record the onset of pain, if this occurred. When a migraine attack ended, patients had to complete a form on the characteristics of the episode (including the presence of PSs not identified prior to the attack). RESULTS: Fifty patients were initially selected. A final total of 34 patients were analyzed, recording 229 attacks. Of whom, 158 (69%) were accompanied by PSs and were recorded prior to the pain onset in 63 (27.5%) cases. A total of 67.6% of the patients were able to predict at least one attack, but only 35.3% were good predictors (>50% of attacks). There were only 11 cases in which a patient erroneously reported their PSs (positive predictive value: 85.1%). Good predictors were not differentiated by any specific clinical characteristic. However, a range of symptoms were particularly predictive; these included photophobia, drowsiness, yawning, increased thirst, and blurred vision. CONCLUSION: A large majority of patients with migraine experienced a PS and were able to predict at least one attack. Besides, only a small percentage of patients were considered as good predictors; however, they could not be characterized by any specific profile. Nonetheless, when patients with migraine believed that they were experiencing PSs, they were frequently correct.

Health-related quality of life in Spanish informal caregivers: gender differences and support received.

PURPOSE: We analyzed gender differences in health-related quality of life (HRQoL) and associated factors between informal male and female caregivers in Spain. It is important because of growing rates of dependent people and dwindling public resources. METHODS: We conducted a cross-sectional study of 610 informal caregivers (265 male and 345 female) using an ad hoc structured questionnaire. We performed a descriptive analysis and used multivariate logistic regression to analyze the risk of poor HRQoL, measured with the EQ-5D-5L, according to caregiver sex, sociodemographic characteristics of caregivers and dependents, caregiving circumstances, and support received. RESULTS: Male caregivers were older than women were, and cared more often for their partners. More women used family caregiving allowance (FCA), respite care services, and counseling services, while more men used paid help, home help, and other forms of instrumental help. Women had worse HRQoL than men, particularly in the pain/discomfort dimension. In addition to older age and poor previous health, caring for a partner (OR = 2.379), for a person with major dependence (OR = 1.917), low social class (OR = 1.634), and low social support (OR = 2.311) were factors associated with poor HRQoL. Receiving FCA was associated with better HRQoL (OR = 0.319). Controlling for all these variables, women had 131% more odds than men to have poor HRQoL. CONCLUSIONS: Male and female caregivers in Spain differ in received support and how their HRQoL is affected. These differences are important to design interventions to promote more equitable sharing of care responsibilities and better caregiver health.

[Current situation of the research on living conditions and health status of elderly people in Spain]. / Situación actual de la investigación sobre las condiciones de vida y el estado de salud de las personas mayores en España.

OBJECTIVE: To analyse the dimensions studied with respect to living and health conditions of the non-institutionalised elderly in the scientific literature in Spain. METHOD: A content analysis based on secondary sources was carried out by literature searches in Pubmed and Embase in Spanish and English. The search strategies combined terms related to older people, health and/or living conditions and with Spain. All studies assessing living and/or health conditions of elderly in Spain were included. Studies analyzing a specific aspect of living or health conditions and those based on institutionalized population were excluded. RESULTS: A total of 14 studies were considered in the content analysis. The studies are usually local, cross-sectional and data collection is done by direct interview. Variability was observed in the aspects analysed about living and health conditions. All studies included: sociodemographic characteristics, health status and lifestyle habits. Issues related to the status of the out-of home environment are poorly analysed. CONCLUSIONS: This work allows knowing the dimensions prioritised in the studies carried out to date about health and living conditions in Spain. It also provides key elements for the development of future research aiming to integrate both living and health conditions of elderly population, both aspects closely related.

Multimorbidity Patterns in Hospitalized Older Patients: Associations among Chronic Diseases and Geriatric Syndromes.

BACKGROUND/OBJECTIVES: The clinical status of older individuals with multimorbidity can be further complicated by concomitant geriatric syndromes. This study explores multimorbidity patterns, encompassing both chronic diseases and geriatric syndromes, in geriatric patients attended in an acute hospital setting. DESIGN: Retrospective observational study. SETTING: Unit of Social and Clinical Assessment (UVSS), Miguel Servet University Hospital (HUMS), Zaragoza (Spain). Year, 2011. PARTICIPANTS: A total of 924 hospitalized patients aged 65 years or older. MEASUREMENTS: Data on patients' clinical, functional, cognitive and social statuses were gathered through comprehensive geriatric assessments. To identify diseases and/or geriatric syndromes that cluster into patterns, an exploratory factor analysis was applied, stratifying by sex. The factors can be interpreted as multimorbidity patterns, i.e., diseases non-randomly associated with each other within the study population. The resulting patterns were clinically assessed by several physicians. RESULTS: The mean age of the study population was 82.1 years (SD 7.2). Multimorbidity burden was lower in men under 80 years, but increased in those over 80. Immobility, urinary incontinence, hypertension, falls, dementia, cognitive decline, diabetes and arrhythmia were among the 10 most frequent health problems in both sexes, with prevalence rates above 20%. Four multimorbidity patterns were identified that were present in both sexes: Cardiovascular, Induced Dependency, Falls and Osteoarticular. The number of conditions comprising these patterns was similar in men and women. CONCLUSION: The existence of specific multimorbidity patterns in geriatric patients, such as the Induced Dependency and Falls patterns, may facilitate the early detection of vulnerability to stressors, thus helping to avoid negative health outcomes such as functional disability.

Preliminary research on 1-(4-bromo-2-nitroimidazol-1-yl)-3-[(18)F]fluoropropan-2-ol as a novel brain hypoxia PET tracer in a rodent model of stroke.

The synthesis of the new radiotracer precursor 4-Br-NITTP and the radiolabeling of the new tracer 1-(4-bromo-2-nitroimidazol-1-yl)-3-[(18)F]fluoropropan-2-ol (4-Br-[(18)F]FMISO) is reported. The cyclic voltammetry behaviour, neuronal cell toxicity, transport through the brain endothelial cell monolayer, in vivo PET imaging and preliminary calculations of the tracer uptake for a rodent model of stroke were studied for the new compound and the results were compared to those obtained with [(18)F]FMISO, the current gold standard PET hypoxia tracer. The new PET brain hypoxia tracer is more easily reduced, has higher CLogP than [(18)F]FMISO and it diffuses more rapidly through brain endothelial cells. The new compound is non-toxic to neuronal cells and it allows the in vivo mapping of stroke in mice with higher sensitivity. 4-Br-[(18)F]FMISO is a good candidate for further development in ischemic stroke.

Robust and Accurate Modeling Approaches for Migraine Per-Patient Prediction from Ambulatory Data.

Migraine is one of the most wide-spread neurological disorders, and its medical treatment represents a high percentage of the costs of health systems. In some patients, characteristic symptoms that precede the headache appear. However, they are nonspecific, and their prediction horizon is unknown and pretty variable; hence, these symptoms are almost useless for prediction, and they are not useful to advance the intake of drugs to be effective and neutralize the pain. To solve this problem, this paper sets up a realistic monitoring scenario where hemodynamic variables from real patients are monitored in ambulatory conditions with a wireless body sensor network (WBSN). The acquired data are used to evaluate the predictive capabilities and robustness against noise and failures in sensors of several modeling approaches. The obtained results encourage the development of per-patient models based on state-space models (N4SID) that are capable of providing average forecast windows of 47 min and a low rate of false positives.

Oct-2 transcription factor binding activity and expression up-regulation in rat cerebral ischaemia is associated with a diminution of neuronal damage in vitro.

Brain plasticity provides a mechanism to compensate for lesions produced as a result of stroke. The present study aims to identify new transcription factors (TFs) following focal cerebral ischaemia in rat as potential therapeutic targets. A transient focal cerebral ischaemia model was used for TF-binding activity and TF-TF interaction profile analysis. A permanent focal cerebral ischaemia model was used for the transcript gene analysis and for the protein study. The identification of TF variants, mRNA analysis, and protein study was performed using conventional polymerase chain reaction (PCR), qPCR, and Western blot and immunofluorescence, respectively. Rat cortical neurons were transfected with small interfering RNA against the TF in order to study its role. The TF-binding analysis revealed a differential binding activity of the octamer family in ischaemic brain in comparison with the control brain samples both in acute and late phases. In this study, we focused on Oct-2 TF. Five of the six putative Oct-2 transcript variants are expressed in both control and ischaemic rat brain, showing a significant increase in the late phase of ischaemia. Oct-2 protein showed neuronal localisation both in control and ischaemic rat brain cortical slices. Functional studies revealed that Oct-2 interacts with TFs involved in important brain processes (neuronal and vascular development) and basic cellular functions and that Oct-2 knockdown promotes neuronal injury. The present study shows that Oct-2 expression and binding activity increase in the late phase of cerebral ischaemia and finds Oct-2 to be involved in reducing ischaemic-mediated neuronal injury.

Rosiglitazone-induced CD36 up-regulation resolves inflammation by PPARγ and 5-LO-dependent pathways.

PPARγ-achieved neuroprotection in experimental stroke has been explained by the inhibition of inflammatory genes, an action in which 5-LO, Alox5, is involved. In addition, PPARγ is known to promote the expression of CD36, a scavenger receptor that binds lipoproteins and mediates bacterial recognition and also phagocytosis. As phagocytic clearance of neutrophils is a requisite for resolution of the inflammatory response, PPARγ-induced CD36 expression might help to limit inflammatory tissue injury in stroke, an effect in which 5-LO might also be involved. Homogenates, sections, and cellular suspensions were prepared from brains of WT and Alox5(-/-) mice exposed to distal pMCAO. BMMs were obtained from Lys-M Cre(+) PPARγ(f/f) and Lys-M Cre(-) PPARγ(f/f) mice. Stereological counting of double-immunofluorescence-labeled brain sections and FACS analysis of cell suspensions was performed. In vivo and in vitro phagocytosis of neutrophils by microglia/macrophages was analyzed. PPARγ activation with RSG induced CD36 expression in resident microglia. This process was mediated by the 5-LO gene, which is induced in neurons by PPARγ activation and at least by one of its products--LXA4--which induced CD36 independently of PPARγ. Moreover, CD36 expression helped resolution of inflammation through phagocytosis, concomitantly to neuroprotection. Based on these findings, in addition to a direct modulation by PPARγ, we propose in brain a paracrine model by which products generated by neuronal 5-LO, such as LXA4, increase the microglial expression of CD36 and promote tissue repair in pathologies with an inflammatory component, such as stroke.

Iron overload, measured as serum ferritin, increases brain damage induced by focal ischemia and early reperfusion.

High levels of iron, measured as serum ferritin, are associated to a worse outcome after stroke. However, it is not known whether ischemic damage might increase ferritin levels as an acute phase protein or whether iron overload affects stroke outcome. The objectives are to study the effect of stroke on serum ferritin and the contribution of iron overload to ischemic damage. Swiss mice were fed with a standard diet or with a diet supplemented with 2.5% carbonyl iron to produce iron overload. Mice were submitted to permanent (by ligature and by in situ thromboembolic models) or transient focal ischemia (by ligature for 1 or 3h). Treatment with iron diet produced an increase in the basal levels of ferritin in all the groups. However, serum ferritin did not change after ischemia. Animals submitted to permanent ischemia had the same infarct volume in the groups studied. However, in mice submitted to transient ischemia followed by early (1h) but not late reperfusion (3h), iron overload increased ischemic damage and haemorrhagic transformation. Iron worsens ischemic damage induced by transient ischemia and early reperfusion. In addition, ferritin is a good indicator of body iron levels but not an acute phase protein after ischemia.

[Cancer Survival between 1995 and 2004 in the Basque Country, Spain].

BACKGROUND: geographic differences described in the prognosis of cancer patients in the Basque Country have been attributed to a different incidence in tumours with different lethality. Therefore, cancer relative survival adjusted by case-mix was included to estimate cancer survival by provinces and health regions, using data from 1995 to 2004. METHODS: a total of 93 585 cases of malignant tumours were identified from a population-based cancer registry. The five-year relative survival (RS) was calculated using Ederer´s method. The five-year relative excess risk (RER) of death was estimated with a generalised linear model, standardized by age and adjusted for sex, date of diagnosis and case-mix. RESULTS: the five-year RS increased from period 1995-1999 to 2000-2004, this latter, with values ranging by health regions between 46-58% and 57-65% in men and women, respectively. There was an excess risk of death in Bizkaia (RER=1.06, CI95%: 1.03-1.09), this same effect being identified in almost all the health regions in the province. In contrast, in Gipuzkoa province, differences were only statistically significant in the Gipuzkoa and Tolosa health regions (RER=1.07; CI95%: 1.02-1.13 and RER=0.91; CI95%: 0.84-0.98, respectively), and even these disappeared after adjusting for potential confounders. CONCLUSIONS: cancer patients of Bizkaia, except for the Uribe health region, presented a worse prognosis.

Regulator of calcineurin 1 (Rcan1) has a protective role in brain ischemia/reperfusion injury.

BACKGROUND: An increase in intracellular calcium concentration [Ca2+]i is one of the first events to take place after brain ischemia. A key [Ca2+]i-regulated signaling molecule is the phosphatase calcineurin (CN), which plays important roles in the modulation of inflammatory cascades. Here, we have analyzed the role of endogenous regulator of CN 1 (Rcan1) in response to experimental ischemic stroke induced by middle cerebral artery occlusion. METHODS: Animals were subjected to focal cerebral ischemia with reperfusion. To assess the role of Rcan1 after stroke, we measured infarct volume after 48 h of reperfusion in Rcan1 knockout (KO) and wild-type (WT) mice. In vitro studies were performed in astrocyte-enriched cortical primary cultures subjected to 3% oxygen (hypoxia) and glucose deprivation (HGD). Adenoviral vectors were used to analyze the effect of overexpression of Rcan1-4 protein. Protein expression was examined by immunohistochemistry and immunoblotting and expression of mRNA by quantitative real-time Reverse-Transcription Polymerase Chain Reaction (real time qRT-PCR). RESULTS: Brain ischemia/reperfusion (I/R) injury in vivo increased mRNA and protein expression of the calcium-inducible Rcan1 isoform (Rcan1-4). I/R-inducible expression of Rcan1 protein occurred mainly in astroglial cells, and in an in vitro model of ischemia, HGD treatment of primary murine astrocyte cultures induced Rcan1-4 mRNA and protein expression. Exogenous Rcan1-4 overexpression inhibited production of the inflammatory marker cyclo-oxygenase 2. Mice lacking Rcan1 had higher expression of inflammation associated genes, resulting in larger infarct volumes. CONCLUSIONS: Our results support a protective role for Rcan1 during the inflammatory response to stroke, and underline the importance of the glial compartment in the inflammatory reaction that takes place after ischemia. Improved understanding of non-neuronal mechanisms in ischemic injury promises novel approaches to the treatment of acute ischemic stroke.

Neurological tests for functional outcome assessment in rodent models of ischaemic stroke.

A critical aspect in all models is the assessment of the final outcome of the modelling procedure. In the case of a focal ischaemic brain injury, apart from the determination of the size of the lesion, another valuable tool is the evaluation of the final functional deficit. Indeed, ischaemic damage leads to the appearance of different degrees of sensoriomotor and cognitive impairments, which may yield useful information on location and size of the lesion and on the efficacy of neuroprotective treatments after the acute injury. In addition, the magnitude of these impairments may also be useful to predict final outcome and to evaluate neuro-restorative therapies in a long-term scenario. To this aim, a wide range of tests has been developed which allow the quantification of all these neurological symptoms. This review intends to compile the most useful behavioural tests designed to assess neurological symptoms in studies of focal experimental cerebral ischemia in rodents induced by middle cerebral artery occlusion, the most commonly used model of ischaemic stroke.

Protective role for type 4 metabotropic glutamate receptors against ischemic brain damage.

We examined the influence of type 4 metabotropic glutamate (mGlu4) receptors on ischemic brain damage using the permanent middle cerebral artery occlusion (MCAO) model in mice and the endothelin-1 (Et-1) model of transient focal ischemia in rats. Mice lacking mGlu4 receptors showed a 25% to 30% increase in infarct volume after MCAO as compared with wild-type littermates. In normal mice, systemic injection of the selective mGlu4 receptor enhancer, N-phenyl-7-(hydroxyimino)cyclopropa[b]chromen-1a-caboxamide (PHCCC; 10 mg/kg, subcutaneous, administered once 30 minutes before MCAO), reduced the extent of ischemic brain damage by 35% to 45%. The drug was inactive in mGlu4 receptor knockout mice. In the Et-1 model, PHCCC administered only once 20 minutes after ischemia reduced the infarct volume to a larger extent in the caudate/putamen than in the cerebral cortex. Ischemic rats treated with PHCCC showed a faster recovery of neuronal function, as shown by electrocorticographic recording and by a battery of specific tests, which assess sensorimotor deficits. These data indicate that activation of mGlu4 receptors limit the development of brain damage after permanent or transient focal ischemia. These findings are promising because selective mGlu4 receptor enhancers are under clinical development for the treatment of Parkinson's disease and other central nervous system disorders.

A mouse model of hemorrhagic transformation by delayed tissue plasminogen activator administration after in situ thromboembolic stroke.

BACKGROUND AND PURPOSE: thrombolytic treatment with tissue plasminogen activator (tPA) improves outcome of patients with stroke who can be treated within 3 hours of symptom onset. However, delayed treatment with tPA leads to increased risk of hemorrhagic transformation and can result in enhanced brain injury. The purpose of this study is to validate a reproducible mouse model of hemorrhagic transformation associated with delayed administration of tPA. METHODS: mice were anesthetized and thrombin was injected into the middle cerebral artery to induce the formation of a clot as described by Orset et al. To induce reperfusion, tPA (10 mg/kg) was intravenously administered 20 minutes or 3 hours after thrombin injection. RESULTS: thrombin produced a clot in 83.1% of the animals, which caused focal ischemia determined 24 hours after the injection. Different degrees of bleeding were found in the middle cerebral artery occlusion group, including hemorrhagic infarction type 1 (HI-1) in 46.2%, hemorrhagic infarction type 2 (HI-2) in 30.8% and parenchymal hemorrhage type 1 in 23.0%. Administration of tPA 20 minutes after the occlusion produced an effective reperfusion in 62.5% of the animals and reduced both infarct volume and appearance of severe hemorrhage (10% nonhemorrhage, 80% HI-1 and 10% HI-2). However, administration of tPA 3 hours after the occlusion led to effective reperfusion in 47.1% of the animals, did not reduce infarct volume, caused hemorrhagic transformation (25% HI-1, 37.5% HI-2, and 37.5% parenchymal hemorrhage type 1), and increased hemorrhage and brain swelling. CONCLUSIONS: we have set up a reproducible mouse model of hemorrhagic transformation associated with delayed administration of tPA similar to that observed in humans.