Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 49
Filtrar
Más filtros

Bases de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
J Neuroinflammation ; 20(1): 295, 2023 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-38082296

RESUMEN

The role of high mobility group box 1 (HMGB1) in inflammation is well characterized in the immune system and in response to tissue injury. More recently, HMGB1 was also shown to initiate an "inflammatory signaling cascade" in the brain parenchyma after a mild and brief disturbance, such as cortical spreading depolarization (CSD), leading to headache. Despite substantial evidence implying a role for inflammatory signaling in prevalent neuropsychiatric disorders such as migraine and depression, how HMGB1 is released from healthy neurons and how inflammatory signaling is initiated in the absence of apparent cell injury are not well characterized. We triggered a single cortical spreading depolarization by optogenetic stimulation or pinprick in naïve Swiss albino or transgenic Thy1-ChR2-YFP and hGFAP-GFP adult mice. We evaluated HMGB1 release in brain tissue sections prepared from these mice by immunofluorescent labeling and immunoelectron microscopy. EzColocalization and Costes thresholding algorithms were used to assess the colocalization of small extracellular vesicles (sEVs) carrying HMGB1 with astrocyte or microglia processes. sEVs were also isolated from the brain after CSD, and neuron-derived sEVs were captured by CD171 (L1CAM). sEVs were characterized with flow cytometry, scanning electron microscopy, nanoparticle tracking analysis, and Western blotting. We found that HMGB1 is released mainly within sEVs from the soma of stressed neurons, which are taken up by surrounding astrocyte processes. This creates conditions for selective communication between neurons and astrocytes bypassing microglia, as evidenced by activation of the proinflammatory transcription factor NF-ĸB p65 in astrocytes but not in microglia. Transmission immunoelectron microscopy data illustrated that HMGB1 was incorporated into sEVs through endosomal mechanisms. In conclusion, proinflammatory mediators released within sEVs can induce cell-specific inflammatory signaling in the brain without activating transmembrane receptors on other cells and causing overt inflammation.


Asunto(s)
Astrocitos , Proteína HMGB1 , Animales , Ratones , Astrocitos/metabolismo , Proteína HMGB1/metabolismo , Inflamación/etiología , Neuronas/metabolismo , Transducción de Señal
2.
J Headache Pain ; 24(1): 96, 2023 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-37495957

RESUMEN

BACKGROUND: Cortical spreading depolarization (CSD), the neurophysiological correlate of the migraine aura, can activate trigeminal pain pathways, but the neurobiological mechanisms and behavioural consequences remain unclear. Here we investigated effects of optogenetically-induced CSDs on headache-related behaviour and neuroinflammatory responses in transgenic mice carrying a familial hemiplegic migraine type 1 (FHM1) mutation. METHODS: CSD events (3 in total) were evoked in a minimally invasive manner by optogenetic stimulation through the intact skull in freely behaving wildtype (WT) and FHM1 mutant mice. Related behaviours were analysed using mouse grimace scale (MGS) scoring, head grooming, and nest building behaviour. Neuroinflammatory changes were investigated by assessing HMGB1 release with immunohistochemistry and by pre-treating mice with a selective Pannexin-1 channel inhibitor. RESULTS: In both WT and FHM1 mutant mice, CSDs induced headache-related behaviour, as evidenced by increased MGS scores and the occurrence of oculotemporal strokes, at 30 min. Mice of both genotypes also showed decreased nest building behaviour after CSD. Whereas in WT mice MGS scores had normalized at 24 h after CSD, in FHM1 mutant mice scores were normalized only at 48 h. Of note, oculotemporal stroke behaviour already normalized 5 h after CSD, whereas nest building behaviour remained impaired at 72 h; no genotype differences were observed for either readout. Nuclear HMGB1 release in the cortex of FHM1 mutant mice, at 30 min after CSD, was increased bilaterally in both WT and FHM1 mutant mice, albeit that contralateral release was more pronounced in the mutant mice. Only in FHM1 mutant mice, contralateral release remained higher at 24 h after CSD, but at 48 h had returned to abnormal, elevated, baseline values, when compared to WT mice. Blocking Panx1 channels by TAT-Panx308 inhibited CSD-induced headache related behaviour and HMGB1 release. CONCLUSIONS: CSDs, induced in a minimally invasive manner by optogenetics, investigated in freely behaving mice, cause various migraine relevant behavioural and neuroinflammatory phenotypes that are more pronounced and longer-lasting in FHM1 mutant compared to WT mice. Prevention of CSD-related neuroinflammatory changes may have therapeutic potential in the treatment of migraine.


Asunto(s)
Depresión de Propagación Cortical , Proteína HMGB1 , Trastornos Migrañosos , Migraña con Aura , Ratones , Animales , Migraña con Aura/genética , Migraña con Aura/metabolismo , Proteína HMGB1/genética , Proteína HMGB1/farmacología , Optogenética , Depresión de Propagación Cortical/fisiología , Modelos Animales de Enfermedad , Trastornos Migrañosos/genética , Ratones Transgénicos , Cefalea , Inflamación , Proteínas del Tejido Nervioso/genética , Conexinas/genética , Conexinas/farmacología
3.
J Trop Pediatr ; 68(2)2022 02 03.
Artículo en Inglés | MEDLINE | ID: mdl-35238388

RESUMEN

OBJECTIVE: Children may be greatly affected by events that increase stress in individuals in general and are reported as the vulnerable groups during the coronavirus disease-19 (COVID-19) pandemic. But most of the studies in the literature investigating the mental effects of the pandemic on children were conducted with healthy children and limited study has evaluated the effect on children diagnosed with COVID-19. The aim of this study is to determine the anxiety level in paediatric patients diagnosed with COVID-19 and the affecting factors. METHODS: This descriptive study was conducted with 292 children aged 8-18 years who were diagnosed with COVID-19. Data were collected using the Descriptive Characteristics Questionnaire and the Screen for Child Anxiety Related Emotional Disorders (SCARED). Interviews were held by phone. RESULTS: Males were 51.4% of participants, the mean age was 16.04 ± 1.93. 84.1% of them had a chronic disease; the transmission source was family/relatives/friends for 41.1%. By social isolation, 49.3% were affected and 33.2% were affected by disease symptoms the most in this process. The most common symptoms were headache (61.6%), and asthenia (59.9%). Mean anxiety scale score was 25.5 ± 14.37. The effect of gender, number of symptoms and transmission source on anxiety score was significant (p < 0.05). CONCLUSION: Paediatric patients diagnosed with COVID-19 were found to have high anxiety levels. It is recommended to re-evaluate the duration of children's social participation and support the management of COVID-19 symptoms that affect their anxiety level.


Asunto(s)
COVID-19 , Adolescente , Ansiedad/epidemiología , COVID-19/epidemiología , Niño , Depresión , Humanos , Masculino , Pandemias , SARS-CoV-2 , Encuestas y Cuestionarios
4.
J Headache Pain ; 23(1): 107, 2022 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-35986251

RESUMEN

BACKGROUND: Unlike the spontaneously appearing aura in migraineurs, experimentally, cortical spreading depression (CSD), the neurophysiological correlate of aura is induced by non-physiological stimuli. Consequently, neural mechanisms involved in spontaneous CSD generation, which may provide insight into how migraine starts in an otherwise healthy brain, remain largely unclear. We hypothesized that CSD can be physiologically induced by sensory stimulation in primed mouse brain. METHODS: Cortex was made susceptible to CSD with partial inhibition of Na+/K+-ATPase by epidural application of a low concentration of Na+/K+-ATPase blocker ouabain, allowing longer than 30-min intervals between CSDs or by knocking-down α2 subunit of Na+/K+-ATPase, which is crucial for K+ and glutamate re-uptake, with shRNA. Stimulation-triggered CSDs and extracellular K+ changes were monitored in vivo electrophysiologically and a K+-sensitive fluoroprobe (IPG-4), respectively. RESULTS: After priming with ouabain, photic stimulation significantly increased the CSD incidence compared with non-stimulated animals (44.0 vs. 4.9%, p < 0.001). Whisker stimulation also significantly increased the CSD incidence, albeit less effectively (14.9 vs. 2.4%, p = 0.02). Knocking-down Na+/K+-ATPase (50% decrease in mRNA) lowered the CSD threshold in all mice tested with KCl but triggered CSDs in 14.3% and 16.7% of mice with photic and whisker stimulation, respectively. Confirming Na+/K+-ATPase hypofunction, extracellular K+ significantly rose during sensory stimulation after ouabain or shRNA treatment unlike controls. In line with the higher CSD susceptibility observed, K+ rise was more prominent after ouabain. To gain insight to preventive mechanisms reducing the probability of stimulus-evoked CSDs, we applied an A1-receptor antagonist (DPCPX) to the occipital cortex, because adenosine formed during stimulation from ATP can reduce CSD susceptibility. DPCPX induced spontaneous CSDs but only small-DC shifts along with suppression of EEG spikes during photic stimulation, suggesting that the inhibition co-activated with sensory stimulation could limit CSD ignition when K+ uptake was not sufficiently suppressed as with ouabain. CONCLUSIONS: Normal brain is well protected against CSD generation. For CSD to be ignited under physiological conditions, priming and predisposing factors are required as seen in migraine patients. Intense sensory stimulation has potential to trigger CSD when co-existing conditions bring extracellular K+ and glutamate concentrations over CSD-ignition threshold and stimulation-evoked inhibitory mechanisms are overcome.


Asunto(s)
Depresión de Propagación Cortical , Trastornos Migrañosos , Migraña con Aura , Adenosina Trifosfatasas/farmacología , Animales , Encéfalo , Depresión de Propagación Cortical/fisiología , Ácido Glutámico , Ratones , Ouabaína/farmacología , ARN Interferente Pequeño/farmacología
5.
Neurobiol Dis ; 156: 105424, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34118418

RESUMEN

Neuroinflammatory changes involving neuronal HMGB1 release and astrocytic NF-κB nuclear translocation occur following cortical spreading depolarization (CSD) in wildtype (WT) mice but it is unknown to what extent this occurs in the migraine brain. We therefore investigated in familial hemiplegic migraine type 1 (FHM1) knock-in mice, which express an intrinsic hyperexcitability phenotype, the extent of neuroinflammation without and after CSD. CSD was evoked in one hemisphere by pinprick (single CSD) or topical KCl application (multiple CSDs). Neuroinflammatory (HMGB1, NF-κB) and neuronal activation (pERK) markers were investigated by immunohistochemistry in the brains of WT and FHM1 mutant mice without and after CSD. Effects of NMDA receptor antagonism on basal and CSD-induced neuroinflammatory changes were examined by, respectively, systemically administered MK801 and ifenprodil or topical MK801 application. In FHM1 mutant mice, CSD caused enhanced neuronal HMGB1 release and astrocytic NF-κB nuclear translocation in the cortex and subcortical areas that were equally high in both hemispheres. In WT mice such effects were only pronounced in the hemisphere in which CSD was induced. Neuroinflammatory responses were associated with pERK expression indicating neuronal activation. Upon CSD, contralateral cortical and striatal HMGB1 release was reduced by topical application of MK801 in the hemisphere contralateral to the one in which CSD was induced. This study reveals that neuroinflammatory activation after CSD is widespread and extends to the contralateral hemisphere, particularly in brains of FHM1 mutant mice. Effective blockade of CSD-induced neuroinflammatory responses in the contralateral hemisphere in FHM1 mice by local NMDA receptor antagonism suggests that neuronal hyperexcitability-related neuroinflammation is relevant in migraine pathophysiology, but possibly also other neurological disorders in which spreading depolarization is involved.


Asunto(s)
Encéfalo/metabolismo , Ataxia Cerebelosa/metabolismo , Depresión de Propagación Cortical/fisiología , Proteína HMGB1/metabolismo , Trastornos Migrañosos/metabolismo , FN-kappa B/metabolismo , Tejido Parenquimatoso/metabolismo , Animales , Astrocitos/metabolismo , Encéfalo/fisiopatología , Ataxia Cerebelosa/genética , Ataxia Cerebelosa/fisiopatología , Femenino , Proteína HMGB1/genética , Humanos , Ratones , Ratones Transgénicos , Trastornos Migrañosos/genética , Trastornos Migrañosos/fisiopatología , FN-kappa B/genética , Tejido Parenquimatoso/fisiopatología
6.
Int J Clin Pract ; 75(5): e14039, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33482048

RESUMEN

AIMS: About 3.5 million Syrian refugees are living within the borders of Turkey. This study examined depression, loneliness and factors influencing refugee children who live outside the camps and attend school in Turkey. METHODS: This was a descriptive study in Sanliurfa, which has the second highest refugee population in Turkey. The sample consisted of 535 students attending 6-8 grades in five schools randomly selected of 18 schools located in the city centre where the Syrian children received their education. Data were collected using the Sociodemographic Characteristics Question Form, the Depression Scale for Children and the UCLA Loneliness Scale. Data were analysed by IBM spss v23. The percentage, average and standard deviation were determined. A linear regression analysis was used to examine the independent variables affecting loneliness and depression scores, and the Backward method was used to include independent variables in the model. Significance level was considered as P < .05. RESULTS: The average age of the children was 13.22 ± 1.33 years and 57.9% female. The average UCLA Loneliness Scale score was 42.95 ± 7.77. About 42% of the children received ≥19 on the depression scale, and 65% of them received ≥40 on the UCLA Loneliness Scale. Independent variables affecting depression score and UCLA loneliness score were analysed by a linear regression analysis. The linear regression model established for depression and UCLA loneliness score was obtained as statistically significant (P < .001). CONCLUSION: Depression and loneliness scores were relatively high in children, particularly those exposed to the devastating impacts of war. These results will make significant contributions to the planning of services to be provided for this group of children.


Asunto(s)
Refugiados , Adolescente , Niño , Depresión/epidemiología , Femenino , Humanos , Soledad , Masculino , Siria , Turquía/epidemiología
7.
J Trop Pediatr ; 67(6)2021 12 08.
Artículo en Inglés | MEDLINE | ID: mdl-34971400

RESUMEN

BACKGROUND: If the mother and infant cannot meet after birth, it is recommended to express milk and give it to the infant. There was evidence indicating that there might be decrease in essential nutrient values in human milk content depending on the expression technique in literature. The goal of this systematic review was to investigate the effect of human milk expression techniques on the macronutrient milk content and establish an evidence base for future studies. METHODS: Studies investigating the effect of human milk expression techniques on milk content were reviewed without year limitations. A literature review was conducted in six electronic databases (MEDLINE, Web of Science, PubMed, ScienceDirect, CINAHL and Cochrane) until 30 May 2021, using the keywords of breast milk expression techniques, milk content and breast milk pumping. RESULTS: From 258 articles initially screened, we included 6 articles in the systematic review. The fat, protein and lactose content of human milk was analyzed in the studies reviewed. It was concluded that there was no significant effect on the protein (9.7-9.8 g/dl and 2.1-2.1 g/dl, respectively) and lactose (6.50-6.53% and 6.1-6.1 g/dl, respectively) content of milk. However, the fat (58.30, 48.81g/l; 2.6-2.2 g/dl) content was affected. CONCLUSIONS: This study investigated the effect of milk expression techniques on the macronutrient content of human milk, and it was concluded that there was no significant effect on the protein and carbohydrate content of milk. However, the fat content was affected. Limitation of this study is that some factors that might affect the content of human milk were not standardized sufficiently in the included studies.


Asunto(s)
Leche Humana , Nutrientes , Femenino , Humanos , Lactante , Lactosa , Madres
8.
J Headache Pain ; 22(1): 55, 2021 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-34112082

RESUMEN

BACKGROUND: Neuroinflammation has an important role in the pathophysiology of migraine, which is a complex neuro-glio-vascular disorder. The main aim of this review is to highlight findings of cortical spreading depolarization (CSD)-induced neuroinflammatory signaling in brain parenchyma from the inflammasome perspective. In addition, we discuss the limited data of the contribution of inflammasomes to other aspects of migraine pathophysiology, foremost the activation of the trigeminovascular system and thereby the generation of migraine pain. MAIN BODY: Inflammasomes are signaling multiprotein complexes and key components of the innate immune system. Their activation causes the production of inflammatory cytokines that can stimulate trigeminal neurons and are thus relevant to the generation of migraine pain. The contribution of inflammasome activation to pain signaling has attracted considerable attention in recent years. Nucleotide-binding domain (NOD)-like receptor family pyrin domain containing 3 (NLRP3) is the best characterized inflammasome and there is emerging evidence of its role in a variety of inflammatory pain conditions, including migraine. In this review, we discuss, from an inflammasome point of view, cortical spreading depolarization (CSD)-induced neuroinflammatory signaling in brain parenchyma, the connection with genetic factors that make the brain vulnerable to CSD, and the relation of the inflammasome with diseases that are co-morbid with migraine, including stroke, epilepsy, and the possible links with COVID-19 infection. CONCLUSION: Neuroinflammatory pathways, specifically those involving inflammasome proteins, seem promising candidates as treatment targets, and perhaps even biomarkers, in migraine.


Asunto(s)
COVID-19 , Trastornos Migrañosos , Humanos , Inflamasomas , Proteína con Dominio Pirina 3 de la Familia NLR , SARS-CoV-2
9.
Ann Neurol ; 83(1): 61-73, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29244233

RESUMEN

OBJECTIVE: Glycogen in astrocyte processes contributes to maintenance of low extracellular glutamate and K+ concentrations around excitatory synapses. Sleep deprivation (SD), a common migraine trigger, induces transcriptional changes in astrocytes, reducing glycogen breakdown. We hypothesize that when glycogen utilization cannot match synaptic energy demand, extracellular K+ can rise to levels that activate neuronal pannexin-1 channels and downstream inflammatory pathway, which might be one of the mechanisms initiating migraine headaches. METHODS: We suppressed glycogen breakdown by inhibiting glycogen phosphorylation with 1,4-dideoxy-1,4-imino-D-arabinitol (DAB) and by SD. RESULTS: DAB caused neuronal pannexin-1 large pore opening and activation of the downstream inflammatory pathway as shown by procaspase-1 cleavage and HMGB1 release from neurons. Six-hour SD induced pannexin-1 mRNA. DAB and SD also lowered the cortical spreading depression (CSD) induction threshold, which was reversed by glucose or lactate supplement, suggesting that glycogen-derived energy substrates are needed to prevent CSD generation. Supporting this, knocking down the neuronal lactate transporter MCT2 with an antisense oligonucleotide or inhibiting glucose transport from vessels to astrocytes with intracerebroventricularly delivered phloretin reduced the CSD threshold. In vivo recordings with a K+ -sensitive/selective fluoroprobe, Asante Potassium Green-4, revealed that DAB treatment or SD caused a significant rise in extracellular K+ during whisker stimulation, illustrating the critical role of glycogen in extracellular K+ clearance. INTERPRETATION: Synaptic metabolic stress caused by insufficient glycogen-derived energy substrate supply can activate neuronal pannexin-1 channels as well as lower the CSD threshold. Therefore, conditions that limit energy supply to synapses (eg, SD) may predispose to migraine attacks, as suggested by genetic studies associating glucose or lactate transporter deficiency with migraine. Ann Neurol 2018;83:61-73.


Asunto(s)
Química Encefálica , Depresión de Propagación Cortical/genética , Glucógeno/metabolismo , Privación de Sueño/fisiopatología , Animales , Arabinosa/farmacología , Astrocitos/efectos de los fármacos , Astrocitos/metabolismo , Conexinas/efectos de los fármacos , Conexinas/metabolismo , Metabolismo Energético , Técnicas de Silenciamiento del Gen , Proteína HMGB1/metabolismo , Iminofuranosas/farmacología , Inyecciones Intraventriculares , Ratones , Transportadores de Ácidos Monocarboxílicos/antagonistas & inhibidores , Proteínas del Tejido Nervioso/efectos de los fármacos , Proteínas del Tejido Nervioso/metabolismo , Oligonucleótidos Antisentido/farmacología , Floretina/farmacología , Potasio/fisiología , Alcoholes del Azúcar/farmacología , Vibrisas/inervación
10.
Adv Exp Med Biol ; 1161: 125-131, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31562627

RESUMEN

Ischemic strokes are caused by one or more blood clots that typically obstruct one of the major arteries in the brain, but frequently also result in leakage of the blood-brain barrier and subsequent hemorrhage. While it has long been known that the enzyme 12/15-lipoxygenase (12/15-LOX) is up-regulated following ischemic strokes and contributes to neuronal cell death, recent research has shown an additional major role for 12/15-LOX in causing this hemorrhagic transformation. These findings have important implications for the use of 12/15-LOX inhibitors in the treatment of stroke.


Asunto(s)
Araquidonato 15-Lipooxigenasa , Isquemia Encefálica , Hemorragia , Accidente Cerebrovascular , Barrera Hematoencefálica/patología , Encéfalo/patología , Isquemia Encefálica/complicaciones , Isquemia Encefálica/fisiopatología , Hemorragia/etiología , Hemorragia/fisiopatología , Humanos , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/fisiopatología
11.
Stroke ; 49(5): 1267-1275, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29669868

RESUMEN

BACKGROUND AND PURPOSE: Reperfusion is the most significant determinant of good outcome after ischemic stroke. However, complete reperfusion often cannot be achieved, despite satisfactory recanalization. We hypothesized that microvascular protection was essential for achieving effective reperfusion and, hence, neuroprotection. To test this hypothesis, we have developed an in vivo model to differentially monitor parenchymal and vascular reactive oxygen species (ROS) formation. By comparing the ROS-suppressing effect of N-tert-butyl-α-phenylnitrone (PBN) with its blood-brain barrier impermeable analog 2-sulfo-phenyl-N-tert-butylnitrone (S-PBN), we assessed the impact of vascular ROS suppression alone on reperfusion and stroke outcome after recanalization. METHODS: The distal middle cerebral artery was occluded for 1 hour by compressing with a micropipette and then recanalized (n=60 Swiss mice). ROS formation was monitored for 1 hour after recanalization by intravital fluorescence microscopy in pial vasculature and cortical parenchyma with topically applied hydroethidine through a cranial window. PBN (100 mg/kg) or S-PBN (156 mg/kg) was administered shortly before recanalization, and suppression of the vascular and parenchymal hydroethidine fluorescence was examined (n=22). Microcirculatory patency, reperfusion, ischemic tissue size, and neurological outcome were also assessed in a separate group of mice 1 to 72 hours after recanalization (n=30). RESULTS: PBN and S-PBN completely suppressed the reperfusion-induced increase in ROS signal within vasculature. PBN readily suppressed ROS produced in parenchyma by 88%. S-PBN also suppressed the parenchymal ROS by 64% but starting 40 minutes later. Intriguingly, PBN and S-PBN comparably reduced the size of ischemic area by 65% and 48% (P>0.05), respectively. S-PBN restored the microvascular patency and perfusion after recanalization, suggesting that its delayed parenchymal antioxidant effect could be secondary to improved microcirculatory reperfusion. CONCLUSIONS: Promoting microvascular reperfusion by protecting vasculature can secondarily reduce parenchymal ROS formation and provide neuroprotection. The model presented can be used to directly assess pharmacological end points postulated in brain parenchyma and vasculature in vivo.


Asunto(s)
Bencenosulfonatos/farmacología , Corteza Cerebral/efectos de los fármacos , Circulación Cerebrovascular/efectos de los fármacos , Óxidos N-Cíclicos/farmacología , Infarto de la Arteria Cerebral Media/metabolismo , Microcirculación/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Piamadre/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Animales , Barrera Hematoencefálica , Corteza Cerebral/irrigación sanguínea , Corteza Cerebral/metabolismo , Corteza Cerebral/patología , Colorantes Fluorescentes , Infarto de la Arteria Cerebral Media/patología , Microscopía Intravital , Masculino , Ratones , Microscopía Fluorescente , Fenantridinas , Piamadre/irrigación sanguínea , Piamadre/metabolismo , Piamadre/patología , Reperfusión
12.
Stroke ; 48(2): 445-451, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-28057806

RESUMEN

BACKGROUND AND PURPOSE: For stroke prevention, patients with atrial fibrillation typically receive oral anticoagulation. The commonly used anticoagulant warfarin increases the risk of hemorrhagic transformation (HT) when a stroke occurs; tissue-type plasminogen activator treatment is therefore restricted in these patients. This study was designed to test the hypothesis that 12/15-lipoxygenase (12/15-LOX) inhibition would reduce HT in warfarin-treated mice subjected to experimental stroke. METHODS: Warfarin was dosed orally in drinking water, and international normalized ratio values were determined using a Coaguchek device. C57BL6J mice or 12/15-LOX knockout mice were subjected to transient middle cerebral artery occlusion with 3 hours severe ischemia (model A) or 2 hours ischemia and tissue-type plasminogen activator infusion (model B), with or without the 12/15-LOX inhibitor ML351. Hemoglobin was determined in brain homogenates, and hemorrhage areas on the brain surface and in brain sections were measured. 12/15-LOX expression was detected by immunohistochemistry. RESULTS: Warfarin treatment resulted in reproducible increased international normalized ratio values and significant HT in both models. 12/15-LOX knockout mice suffered less HT after severe ischemia, and ML351 reduced HT in wild-type mice. When normalized to infarct size, ML351 still independently reduced hemorrhage. HT after tissue-type plasminogen activator was similarly reduced by ML351. CONCLUSIONS: In addition to its benefits in infarct size reduction, 12/15-LOX inhibition also may independently reduce HT in warfarin-treated mice. ML351 should be further evaluated as stroke treatment in anticoagulated patients suffering a stroke, either alone or in conjunction with tissue-type plasminogen activator.


Asunto(s)
Anticoagulantes/toxicidad , Araquidonato 12-Lipooxigenasa/deficiencia , Araquidonato 12-Lipooxigenasa/metabolismo , Araquidonato 15-Lipooxigenasa/deficiencia , Araquidonato 15-Lipooxigenasa/metabolismo , Hemorragia Cerebral/enzimología , Accidente Cerebrovascular/enzimología , Warfarina/toxicidad , Animales , Hemorragia Cerebral/inducido químicamente , Hemorragia Cerebral/tratamiento farmacológico , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/uso terapéutico , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Accidente Cerebrovascular/tratamiento farmacológico
13.
Int J Neurosci ; 125(12): 941-6, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25340256

RESUMEN

Under pathological conditions such as brain trauma, subarachnoid hemorrhage and stroke, cortical spreading depression (CSD) or peri-infarct depolarizations contribute to brain damage in animal models of neurological disorders as well as in human neurological diseases. CSD causes transient megachannel opening on the neuronal membrane, which may compromise neuronal survival under pathological conditions. Poloxamer-188 (P-188) and citicoline are neuroprotectants with membrane sealing properties. The aim of this study is to investigate the effect of P-188 and citicoline on the neuronal megachannel opening induced by CSD in the mouse brain. We have monitored megachannel opening with propidium iodide, a membrane impermeable fluorescent dye and, demonstrate that P-188 and citicoline strikingly decreased CSD-induced neuronal PI influx in cortex and hippocampal dentate gyrus. Therefore, these agents may be providing neuroprotection by blocking megachannel opening, which may be related to their membrane sealing action and warrant further investigation for treatment of traumatic brain injury and ischemic stroke.


Asunto(s)
Encéfalo/efectos de los fármacos , Depresión de Propagación Cortical/efectos de los fármacos , Citidina Difosfato Colina/farmacología , Nootrópicos/farmacología , Poloxámero/farmacología , Análisis de Varianza , Animales , Encéfalo/irrigación sanguínea , Circulación Cerebrovascular/efectos de los fármacos , Ratones
14.
Ann Neurol ; 73(1): 129-35, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23192915

RESUMEN

Targeting newly identified damage pathways in the ischemic brain can help to circumvent the currently severe limitations of acute stroke therapy. Here we show that the activity of 12/15-lipoxygenase was increased in the ischemic mouse brain, and 12/15-lipoxygenase colocalized with a marker for oxidized lipids, MDA2. This colocalization was also detected in the brain of 2 human stroke patients, where it also coincided with increased apoptosis-inducing factor. A novel inhibitor of 12/15-lipoxygenase, LOXBlock-1, protected neuronal HT22 cells against oxidative stress. In a mouse model of transient focal ischemia, the inhibitor reduced infarct sizes both 24 hours and 14 days poststroke, with improved behavioral parameters. Even when treatment was delayed until at least 4 hours after onset of ischemia, LOXBlock-1 was protective. Furthermore, it reduced tissue plasminogen activator-associated hemorrhage in a clot model of ischemia/reperfusion. This study establishes inhibition of 12/15-lipoxygenase as a viable strategy for first-line stroke treatment.


Asunto(s)
Araquidonato 12-Lipooxigenasa/metabolismo , Araquidonato 15-Lipooxigenasa/metabolismo , Inhibidores de la Lipooxigenasa/uso terapéutico , Accidente Cerebrovascular/tratamiento farmacológico , Accidente Cerebrovascular/enzimología , Anciano , Animales , Femenino , Humanos , Inhibidores de la Lipooxigenasa/administración & dosificación , Masculino , Ratones , Persona de Mediana Edad , Resultado del Tratamiento
15.
J Clin Nurs ; 23(3-4): 524-30, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23710541

RESUMEN

AIMS AND OBJECTIVES: To detect traditional methods applied for the treatment of newborn jaundice by mothers in Turkey. BACKGROUND: Traditional methods are generally used in our society. Instead of using medical services, people often use already-known traditional methods to treat the disease. In such cases, the prognosis of the disease generally becomes worse, the treatment period longer and healthcare costs higher, and more medicine is used. DESIGN: A cross-sectional descriptive study. METHODS: The participants of this study were 229 mothers with newborn babies aged 0-28 days in one university hospital and one public children's hospital in Sanliurfa. The study was conducted between March and May 2012. In this research, the Beliefs and Traditional Methods of Mothers for Jaundice Questionnaire, which was formed by searching the relevant literature, is used as a data collection tool. The data are evaluated by percentage distributions. RESULTS: Mothers apply conventional practices in cases of health problems such as jaundice, and application of these methods is important to mothers. Moreover, mothers reported applying hazardous conventional methods in cases of neonatal jaundice, such as cutting the area between the baby's eyebrows with a blade, cutting the back of the ear and the body and burning the body, which are not applied in different cultures. CONCLUSIONS: Education regarding the effects of conventional methods being applied in families should be provided, and the results of this study should serve to guide further studies in assessing the effects of such education. RELEVANCE TO CLINICAL PRACTICE: This approach can support beneficial practices involving individual care and prevent the negative health effects of hazardous practices.


Asunto(s)
Ictericia/terapia , Medicina Tradicional , Adulto , Estudios Transversales , Femenino , Humanos , Recién Nacido , Embarazo , Turquía , Adulto Joven
16.
Psychiatry ; 87(1): 65-81, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38227492

RESUMEN

ObjectiveThe purpose of this study was to compare the peer bullying of refugee and non-refugee adolescents, and to explore the association between bullying victimization and psychiatric symptoms among Syrian adolescent refugees in the Southeast Anatolia region of Turkey. Methods: The sample of the study consists of 217 adolescents in the 13-17 age group who are school-going, 102 refugee adolescents, and 115 non-refugee adolescents. The study data was obtained using the Sociodemographic Characteristics Questionnaire developed by the researchers, Olweus Bully/Victim Questionnaire (OBVQ) and Depression Anxiety Stress Scale 42 (DASS-42). A structural equation model was used to assess the association between bullying victimization and depressive symptoms, while also considering mediation by stress and anxiety. Results: In this study, 44.1% of refugee adolescents reported experiencing at least one bullying victimization, while this rate was 27.8% in the non-refugee group, and this difference was found statistically significant. The logistic regression analysis revealed that poor school performance was a risk factor for bullying victimization in refugee adolescent. Moreover, the structural equation model analysis revealed that bullying victimization significantly increased the stress level in refugee adolescents, and depressive symptoms were significantly affected by stress and anxiety levels. Conclusion: Taking into consideration that bullying victimization is a significant problem among Syrian refugee adolescents; anti-bullying programmes should be implemented as this may improve the mental health of Syrian refugee adolescents.


Asunto(s)
Acoso Escolar , Víctimas de Crimen , Refugiados , Humanos , Adolescente , Turquía/epidemiología , Siria , Análisis de Clases Latentes , Acoso Escolar/psicología , Víctimas de Crimen/psicología
17.
Stroke ; 44(10): 2883-90, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23920016

RESUMEN

BACKGROUND AND PURPOSE: Contrast medium extravasation (CE) in intracerebral hemorrhage (ICH) is a marker of ongoing bleeding and a predictor of hematoma expansion. The aims of the study were to establish an ICH model in which CE can be quantified, characterized in ICH during warfarin and dabigatran anticoagulation, and to evaluate effects of prothrombin complex concentrates on CE in warfarin-associated ICH. METHODS: CD1-mice were pretreated orally with warfarin, dabigatran, or vehicle. Prothrombin complex concentrates were administered in a subgroup of warfarin-treated mice. ICH was induced by stereotactic injection of collagenase VIIs into the right striatum. Contrast agent (350 µL Isovue 370 mg/mL) was injected intravenously after ICH induction (2-3.5 hours). Thirty minutes later, mice were euthanized, and CE was measured by quantifying the iodine content in the hematoma using dual-energy computed tomography. RESULTS: The optimal time point for contrast injection was found to be 3 hours after ICH induction, allowing detection of both an increase and a decrease of CE using dual-energy computed tomography. CE was higher in the warfarin group compared with the controls (P=0.002). There was no significant difference in CE between dabigatran-treated mice and controls. CE was higher in the sham-treated warfarin group than in the prothrombin complex concentrates-treated warfarin group (P<0.001). CONCLUSIONS: Dual-energy computed tomography allows quantifying CE, as a marker of ongoing bleeding, in a model of anticoagulation-associated ICH. Dabigatran induces less CE in ICH than warfarin and consequently reduces risks of hematoma expansion. This constitutes a potential safety advantage of dabigatran over warfarin. Nevertheless, in case of warfarin anticoagulation, prothrombin complex concentrates reduce this side effect.


Asunto(s)
Anticoagulantes/efectos adversos , Antitrombinas/efectos adversos , Bencimidazoles/efectos adversos , Factores de Coagulación Sanguínea/farmacología , Hemorragia Cerebral , Medios de Contraste/farmacología , Yopamidol/farmacología , Imagen Radiográfica por Emisión de Doble Fotón/métodos , Warfarina/efectos adversos , beta-Alanina/análogos & derivados , Animales , Anticoagulantes/farmacología , Antitrombinas/farmacología , Bencimidazoles/farmacología , Hemorragia Cerebral/inducido químicamente , Hemorragia Cerebral/diagnóstico por imagen , Hemorragia Cerebral/tratamiento farmacológico , Dabigatrán , Masculino , Ratones , Factores de Tiempo , Warfarina/farmacología , beta-Alanina/efectos adversos , beta-Alanina/farmacología
19.
Noro Psikiyatr Ars ; 60(2): 117-123, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37287564

RESUMEN

Introduction: Idiopathic intracranial hypertension (IIH) symptoms include headache, blurred vision, and papilledema which may lead to permanent vision loss unless diagnosed and treated. Definitive diagnosis of IIH usually requires the measurement of intracranial pressure (ICP) via lumbar puncture (LP) which is an invasive and unwanted technique for patients. In our study, optic nerve sheath diameters (ONSD) were measured before and after lumbar puncture in IIH patients and the relationship of these measurements with ICP changes was evaluated as well as the effect of decreasing cerebrospinal fluid (CSF) pressure after a lumbar puncture on ONSD. Thus, we want to investigate whether optic nerve ultrasonography (USG) is a useful tool instead of the invasive LP for the diagnosis of IIH. Methods: A total of 25 patients who applied to the neurology clinics of Ankara Numune Training and Research Hospital between May 2014 and December 2015 and were diagnosed with IIH were included in the study. The control group consisted of 22 individuals who applied with complaints other than headaches, visual impairment or tinnitus. Optic nerve sheath diameters were measured from both eyes before and after the LP. After pre-LP measurements were taken, opening and closing CSF pressure was measured. In the control group, ONSD was measured with optic USG. Results: Mean age of the IIH group and the control group was determined as 34.8±11.5 and 45.8±13.3 years, respectively. In the patient group, mean CSF opening pressure was 33.9±8.0 cm H2O and mean closing pressure was 18.1±4.7 cm H2O. Mean ONSD measured pre-LP was 7.1±1.0 mm in the right eye and 6.9±0.7 mm in the left eye, while mean post-LP ONSD was 6.7±0.9 mm in the right eye and 6.4±0.8 mm in the left eye. There was a statistically significant difference between ONSD values before and after the LP (p=0.006 for the right eye, p<0.001 for the left eye). In the control group, mean ONSD was 5.4±0.7 mm in the right eye and 5.5±0.6 mm in the left eye, and a statistically significant difference was found between ONSD values before and after the LP (p<0.001 for the right eye and left eye). A significant positive correlation was determined between left ONSD measurements before the LP and CSF opening pressure (r=0.501, p=0.011). Conclusions: In the present study, it was found that ONSD measurement by optic USG significantly displays increased ICP, and decreasing pressure via LP is rapidly reflecting ONSD measurement. Based on these findings, it is suggested that ONSD measurements by optic USG, a non-invasive method, can be used in the diagnosis and follow-up of IIH patients.

20.
Front Cell Neurosci ; 17: 1277268, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37822799

RESUMEN

Introduction: Lipoxygenases (LOXs) have essential roles in stroke, atherosclerosis, diabetes, and hypertension. 12/15-LOX inhibition was shown to reduce infarct size and brain edema in the acute phase of experimental stroke. However, the significance of 12/15-LOX on neuroinflammation, which has an essential role in the pathophysiology of stroke, has not been clarified yet. Methods: In this study, ischemia/recanalization (I/R) was performed by occluding the proximal middle cerebral artery (pMCAo) in mice. Either the 12/15-LOX inhibitor (ML351, 50 mg/kg) or its solvent (DMSO) was injected i.p. at recanalization after 1 h of occlusion. Mice were sacrificed at 6, 24, and 72-h after ischemia induction. Infarct volumes were calculated on Nissl-stained sections. Neurological deficit scoring was used for functional analysis. Lipid peroxidation was determined by the MDA assay, and the inflammatory cytokines IL-6, TNF-alpha, IL-1beta, IL-10, and TGF-beta were quantified by ELISA. The inflammasome proteins NLRP1 and NLRP3, 12/15-LOX, and caspase-1 were detected with immunofluorescence staining. Results: Infarct volumes, neurological deficit scores, and lipid peroxidation were significantly attenuated in ML351-treated groups at 6, 24, and 72-h. ELISA results revealed that the pro-inflammatory cytokines IL-1beta, IL-6, and TNF-alpha were significantly decreased at 6-h and/or 24-h of I/R, while the anti-inflammatory cytokines IL-10 and TNF-alpha were increased at 24-h or 72-h of ML351 treatment. NLRP1 and NLRP3 immunosignaling were enhanced at three time points after I/R, which were significantly diminished by the ML351 application. Interestingly, NLRP3 immunoreactivity was more pronounced than NLRP1. Hence, we proceeded to study the co-localization of NLRP3 immunoreactivity with 12/15-LOX and caspase-1, which indicated that NLRP3 was co-localized with 12/15-LOX and caspase-1 signaling. Additionally, NLRP3 was found in neurons at all time points but in non-neuronal cells 72 h after I/R. Discussion: These results suggest that 12/15-LOX inhibition suppresses ischemia-induced inflammation in the acute and subacute phases of stroke via suppressing inflammasome activation. Understanding the mechanisms underlying lipid peroxidation and its associated pathways, like inflammasome activation, may have broader implications for the treatment of stroke and other neurological diseases characterized by neuroinflammation.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA