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1.
J Perianesth Nurs ; 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38678460

RESUMO

PURPOSE: The purpose of this study is to cross-culturally adapt the Post Hospitalization Behavior Questionnaire for Ambulatory Surgery (PHBQ-AS) to Turkish and test its validity and reliability. DESIGN: This is a methodological study. METHODS: This study was conducted with 121 children aged 1 to 12 years who underwent ambulatory surgery. The data of the study were collected using a Descriptive Information Form, PHBQ-AS, and the Parents' Postoperative Pain Measure. Data analysis and evaluation were performed using factor analysis, Cronbach's α analysis, item-total score correlation analysis, content validity, construct validity, and concurrent validity. FINDINGS: PHBQ-AS showed a high level of internal consistency (Cronbach's α = 0.801). The item-total correlation values of PHBQ-AS were found to be 0.458 to 0.753. PHBQ-AS was determined to be a single-factor scale explaining 66% of the variance in the examined variable. PHBQ-AS and Parents' Postoperative Pain Measure scores were moderately correlated. CONCLUSIONS: The Turkish version of PHBQ-AS was highly valid and reliable for the Turkish population. A recommendation for health care professionals in Turkey is to use the PHBQ-AS scale to evaluate posthospitalization behavioral changes in children who are admitted for ambulatory surgery.

2.
Can J Physiol Pharmacol ; 101(2): 65-73, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36524681

RESUMO

Antenatal steroid administration to pregnant women at risk of prematurity provides pulmonary maturation in infants, while it has limited effects on incidence of bronchopulmonary dysplasia (BPD), the clinical expression of hyperoxia-induced lung injury (HILI). Cytidine-5'-diphosphate choline (CDP-choline) was shown to alleviate HILI when administered to newborn rats. Therefore, we investigated effects of maternal administration of CDP-choline, alone or in combination with betamethasone, on lung maturation in neonatal rats subjected to HILI immediately after birth. Pregnant rats were randomly assigned to one of the four treatments: saline (1 mL/kg), CDP-choline (300 mg/kg), betamethasone (0.4 mg/kg), or CDP-choline plus betamethasone (combination therapy). From postnatal day 1 to 11, pups born to mothers in the same treatment group were pooled and randomly assigned to either normoxia or hyperoxia group. Biochemical an d histopathological effects of CDP-choline on neonatal lung tissue were evaluated. Antenatal CDP-choline treatment increased levels of phosphatidylcholine and total lung phospholipids, decreased apoptosis, and improved alveolarization. The outcomes were further improved with combination therapy compared to the administration of CDP-choline or betamethasone alone. These results demonstrate that antenatal CDP-choline treatment provides benefit in experimental HILI either alone or more intensively when administered along with a steroid, suggesting a possible utility for CDP-choline against BPD.


Assuntos
Displasia Broncopulmonar , Hiperóxia , Lesão Pulmonar , Animais , Ratos , Feminino , Gravidez , Humanos , Recém-Nascido , Citidina Difosfato Colina/farmacologia , Citidina Difosfato Colina/uso terapêutico , Lesão Pulmonar/etiologia , Lesão Pulmonar/prevenção & controle , Lesão Pulmonar/metabolismo , Hiperóxia/complicações , Hiperóxia/metabolismo , Hiperóxia/patologia , Animais Recém-Nascidos , Pulmão/metabolismo , Betametasona/farmacologia , Betametasona/uso terapêutico , Betametasona/metabolismo , Displasia Broncopulmonar/etiologia , Displasia Broncopulmonar/prevenção & controle
3.
Omega (Westport) ; : 302228221123154, 2022 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-36036182

RESUMO

We aimed to examine the relation between the fear of COVID-19 and depression, anxiety and burnout of intensive carenurses. This cross-sectional and descriptive research was conducted with 116 intensive care nurses. The data were obtained with a web-based questionnaire created with the "Descriptive Information Form", "COVID-19 Fear Scale", "Depression, Anxiety and Stress Scale Short Form" and "Burnout Short Version". A significant positive correlation was found between depression (r = 0.498, p < .001), anxiety (r = 0.633, p < .001), stress (r = 0.589, p < .001) and burnout (r = 0.299, p = .001) levels of intensive care nurses with a mean age of 30.18 ± 6.55 with the help of the "COVID-19 Fear Scale". It was determined that the mental health of intensive care nurses was at risk and they reached the level of burnout. Intensive care nurses should be supported in understanding the symptoms of psychological problems and in stress management, personal and professional self-care. Receiving professional mental health support when necessary.

4.
Turk J Med Sci ; 50(8): 2059-2066, 2020 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-32490647

RESUMO

Background/aim: Premature birth is a major problem that results in an increased risk of mortality and morbidity. The management of such infants consists of supraphysiological oxygen therapy, which affects brain development due, in part, to the deterioration caused by reactive oxygen species (ROS). We showed previously that exogenously administered uridine provides neuroprotection in a neonatal rat model of hyperoxic brain injury. Hence, the aim of the present study was to investigate the effects of uridine on ROS in the same setting. Materials and methods: Hyperoxic brain injury was induced by subjecting a total of 53 six-day-old rat pups to 80% oxygen (the hyperoxia group) for a period of 48 h. The pups in the normoxia group continued breathing room air (21% oxygen). Normoxia + saline or hyperoxia + saline or hyperoxia + uridine 100 mg/kg or hyperoxia + uridine 300 mg/kg or hyperoxia + uridine 500 mg/kg was injected intraperitoneally (i. p.) 15 min prior to the hyperoxia procedure. The pups were decapitated and the brains were homogenized to analyze superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), myeloperoxidase (MPO), and malondialdehyde (MDA) enzymes as well as DJ-1 (protein deglycase DJ-1) ­ an oxidative stress-sensitive protein. Results: Hyperoxia-induced may cause overproduction of oxygen radicals and the oxidant/antioxidant balance may be disturbed in the brain. Brain MPO and MDA levels were significantly increased in saline-receiving pups exposed to hyperoxia. Brain SOD and GSH-Px levels were significantly decreased in saline-receiving pups exposed to hyperoxia. Our results showed that uridine administration prevented the hyperoxia-induced decrease in SOD and GSH-Px while counteracting the hyperoxia-induced increase in MPO and MDA in a dose-dependent manner. Uridine also increased the DJ-1 levels in brains of rat pups subjected to hyperoxia. Conclusion: These data suggest that uridine exhibits antioxidative properties which may mediate the protective effects of uridine in a neonatal rat model of hyperoxic brain injury.


Assuntos
Antioxidantes/farmacologia , Lesões Encefálicas/tratamento farmacológico , Hiperóxia/fisiopatologia , Fármacos Neuroprotetores/farmacologia , Animais , Animais Recém-Nascidos , Lesões Encefálicas/etiologia , Lesões Encefálicas/fisiopatologia , Modelos Animais de Doenças , Glutationa Peroxidase/efeitos dos fármacos , Glutationa Peroxidase/metabolismo , Hiperóxia/complicações , Malondialdeído/metabolismo , Peroxidase/efeitos dos fármacos , Peroxidase/metabolismo , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase , Uridina
5.
Brain Res ; 1676: 57-68, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-28919465

RESUMO

Exposure to excessive oxygen in survivors of preterm birth is one of the factors that underlie the adverse neurological outcome in later life. Various pathological changes including enhanced apoptotic activity, oxidative stress and inflammation as well as decreased neuronal survival has been demonstrated in animal models of neonatal hyperoxia. The aim of the present study was to investigate the effect of administering uridine, an anti-apoptotic agent, on cellular, molecular and behavioral consequences of hyperoxia-induced brain damage in a neonatal rat model. For five days from birth, rat pups were either subjected continuously to room air (21% oxygen) or hyperoxia (80% oxygen) and received daily intraperitoneal (i.p.) injections of saline (0.9% NaCl) or uridine (500mg/kg). Two-thirds of all pups were sacrificed on postnatal day 5 (P5) in order to investigate apoptotic cell death, myelination and number of surviving neurons. One-thirds of pups were raised through P40 in order to evaluate early reflexes, sensorimotor coordination and cognitive functions followed by investigation of neuron count and myelination. We show that uridine treatment reduces apoptotic cell death and hypomyelination while increasing the number of surviving neurons in hyperoxic pups on P5. In addition, uridine enhances learning and memory performances in periadolescent rats on P40. These data suggest that uridine administered during the course of hyperoxic insult enhances cognitive functions at periadolescent period probably by reducing apoptotic cell death and preventing hypomyelination during the neonatal period in a rat model of hyperoxia-induced brain injury.


Assuntos
Lesões Encefálicas/tratamento farmacológico , Encéfalo/crescimento & desenvolvimento , Disfunção Cognitiva/prevenção & controle , Hiperóxia/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Uridina/farmacologia , Animais , Animais Recém-Nascidos , Apoptose/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Encéfalo/fisiopatologia , Lesões Encefálicas/patologia , Lesões Encefálicas/fisiopatologia , Lesões Encefálicas/psicologia , Contagem de Células , Sobrevivência Celular/efeitos dos fármacos , Disfunção Cognitiva/patologia , Disfunção Cognitiva/fisiopatologia , Modelos Animais de Doenças , Feminino , Hiperóxia/patologia , Hiperóxia/fisiopatologia , Hiperóxia/psicologia , Deficiências da Aprendizagem/patologia , Deficiências da Aprendizagem/fisiopatologia , Deficiências da Aprendizagem/prevenção & controle , Masculino , Bainha de Mielina/efeitos dos fármacos , Bainha de Mielina/patologia , Neurônios/efeitos dos fármacos , Neurônios/patologia , Distribuição Aleatória , Ratos Sprague-Dawley
6.
Brain Res ; 1659: 81-87, 2017 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-28126402

RESUMO

Hypoxic-ischemic encephalopathy (HIE), is the most common brain disorder in neonates during the perinatal period, which, to date, can only be managed to some extent by hypothermia. Uridine is the principal circulating pyrimidine in humans which is utilized as a precursor for membrane phospholipid biosynthesis. Uridine has recently been shown to provide clinical benefit in treatment of Alzheimer's disease due to its involvement in increasing number of brain synapses along with other phospholipid precursors. We previously showed that uridine treatment ameliorated brain damage by reducing apoptosis in a rat model of neonatal HIE. The aim of the present study was to investigate the effects of uridine administration on cognitive functions during periadolescent period in rats subjected to hypoxic-ischemic (HI) brain damage in neonatal period. Male newborn rats were subjected to HI insult on postnatal day 7 (P7) and were injected intraperitoneally with either saline or uridine (500mg/kg) for three consecutive days. Part of pups in each group were sacrificed on P10 to collect brain samples for active Caspase-3 analyses and the remaining pups were raised through P40 to evaluate early reflexes, sensorimotor coordination and learning and memory functions by Negative Geotaxis (NG), Beam Walking (BW) and Morris Water Maze (MWM) tasks, respectively. Confirming our previous findings, we showed that uridine administration reduced apoptotic cell damage on P10. No significant difference was observed between uridine and saline groups in early reflexes or sensorimotor coordination. On the other hand, rats receiving uridine displayed improved learning and memory in MWM during periadolescent period. We conclude that uridine treatment improves learning and memory in the long term by, probably, reducing apoptotic cell death in early newborn period. This is the first study to show beneficial cognitive effects of uridine in rats with brain damage.


Assuntos
Cognição/efeitos dos fármacos , Hipóxia-Isquemia Encefálica/tratamento farmacológico , Nootrópicos/farmacologia , Uridina/farmacologia , Animais , Animais Recém-Nascidos , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Caspase 3/metabolismo , Cognição/fisiologia , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Hipóxia-Isquemia Encefálica/metabolismo , Hipóxia-Isquemia Encefálica/psicologia , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Aprendizagem em Labirinto/fisiologia , Atividade Motora/efeitos dos fármacos , Atividade Motora/fisiologia , Ratos Sprague-Dawley
7.
Restor Neurol Neurosci ; 33(5): 777-84, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26410212

RESUMO

PURPOSE: A significant cause of neurological disability in newborns is hypoxic-ischemic encephalopathy (HIE), a disorder which involves an enhancement in histone deacetylase (HDAC) activity among underlying pathological mechanisms. We showed recently that exogenous administration of uridine to newborn rats with HIE reduced brain injury in a dose-dependent manner. The present study was performed to investigate whether uridine modulates histone acetylation/deacetylation balance in a neonatal rat model of HIE. METHODS: Newborn rats that were subjected to hypoxic-ischemic (HI) insult on postnatal day 7 (P7) were injected intraperitoneally with either saline or uridine (500 mg/kg) for three consecutive days. One day after completion of treatment, brains of pups were collected for evaluation of brain infarct volume, apoptosis, HDAC activity and acetylated-Histone H3 (Ac-H3) and H4 (Ac-H4) protein levels. RESULTS: Results revealed that uridine administration reduced infarct volume, active Caspase-3 levels and HDAC activity while increasing the expressions of Ac-H3 and Ac-H4 proteins. CONCLUSIONS: We conclude that one mechanism by which uridine provides neuroprotection in neonatal rat HIE model involves reduction in HDAC activity.


Assuntos
Encéfalo/efeitos dos fármacos , Inibidores de Histona Desacetilases/farmacologia , Hipóxia-Isquemia Encefálica/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Uridina/farmacologia , Animais , Animais Recém-Nascidos , Western Blotting , Encéfalo/enzimologia , Encéfalo/patologia , Caspase 3/metabolismo , Modelos Animais de Doenças , Feminino , Histona Desacetilases/metabolismo , Hipóxia-Isquemia Encefálica/enzimologia , Hipóxia-Isquemia Encefálica/patologia , Injeções Intraperitoneais , Masculino , Distribuição Aleatória , Ratos Sprague-Dawley , Resultado do Tratamento
8.
Neurosci Lett ; 542: 65-70, 2013 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-23458674

RESUMO

Neonatal hypoxic-ischemic encephalopathy (HIE) is a major cause of neurological disability requiring newer therapeutic strategies. Uridine is the principal circulating pyrimidine in humans and a substrate for nucleotides and membrane phospholipids. The objective of this study was to investigate the effects of uridine in a neonatal rat model of HIE. Rat pups subjected to hypoxic-ischemic insult on postnatal day 7 were injected intraperitoneally with either saline or uridine (100, 300 or 500mg/kg) for three consecutive days and brains were collected for evaluation of brain infarct volume and apoptosis. Compared with Control group, uridine at 300 and 500mg/kg doses significantly reduced percent infarct volume, TUNEL(+) cell ratio and active Caspase-3 immunoreactivity in the cortex, as well as in CA1 and CA3 regions of the hippocampus. Uridine (300 and 500mg/kg) also decreased active Caspase-3 expression in the ipsilateral hemisphere. These data indicate that uridine dose-dependently reduces brain injury in a rat model of neonatal HIE by decreasing apoptosis.


Assuntos
Encéfalo/efeitos dos fármacos , Hipóxia-Isquemia Encefálica/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Uridina/uso terapêutico , Animais , Animais Recém-Nascidos , Apoptose , Encéfalo/patologia , Infarto Encefálico/tratamento farmacológico , Infarto Encefálico/patologia , Caspase 3/metabolismo , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/enzimologia , Córtex Cerebral/patologia , Hipóxia-Isquemia Encefálica/patologia , Ratos , Ratos Sprague-Dawley
9.
Restor Neurol Neurosci ; 30(5): 435-44, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22751353

RESUMO

PURPOSE: The objective of this study was to compare the effects of two neuroprotective agents; melatonin, a free radical scavenger and topiramate, AMPA/kainate receptor antagonist, administered alone or in combination in neonatal hypoxic-ischemic model. METHODS: After being anesthetized, 7-day-old pups underwent ischemia followed by exposure to hypoxia. The pups were divided into 4 groups in order to receive the vehicle, melatonin, topiramate and combination of topiramate and melatonin. These were administered intraperitoneally for three times; the first before ischemia, the second after hypoxia and the third 24 hours after the second dose. After sacrification, infarct volume and apoptosis were evaluated. RESULTS: Percent infarcted brain volume was significantly reduced in rats which received drugs compared with those which received the vehicle. The number of TUNEL positive cells per unit area in hippocampus and cortex were markedly reduced in drug treated groups compared with control group. No significant differences were found regarding percent infarcted brain volume and number of TUNEL positive cells among drug-treated groups. CONCLUSIONS: Melatonin and topiramate, administered either alone or in combination significantly reduced the percent infarcted brain volume and number of TUNEL positive cells suggesting that these agents may confer benefit in treatment of infants with hypoxic-ischemic encephalopathy.


Assuntos
Frutose/análogos & derivados , Hipóxia-Isquemia Encefálica/tratamento farmacológico , Hipóxia-Isquemia Encefálica/prevenção & controle , Melatonina/administração & dosagem , Fármacos Neuroprotetores/administração & dosagem , Análise de Variância , Animais , Animais Recém-Nascidos , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Infarto Encefálico/etiologia , Infarto Encefálico/patologia , Infarto Encefálico/prevenção & controle , Caspase 3/metabolismo , Contagem de Células , Morte Celular/efeitos dos fármacos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Esquema de Medicação , Quimioterapia Combinada , Feminino , Frutose/administração & dosagem , Hipóxia-Isquemia Encefálica/complicações , Marcação In Situ das Extremidades Cortadas , Masculino , Ratos , Topiramato
10.
Neonatology ; 99(4): 302-10, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21135566

RESUMO

BACKGROUND: Perinatal hypoxia-ischemia is a major cause of mortality and long-term neurological deficits. OBJECTIVES: The objective of this study was to compare the effects of two neuroprotective agents; magnesium sulfate and melatonin, administered alone or in combination, on brain infarct volume and TUNEL positivity in a neonatal hypoxic-ischemic (HI) rat model. METHODS: After being anesthetized, 7-day-old pups (n = 80) underwent ischemia followed by exposure to hypoxia for 2 h. The pups were then divided equally and randomly into 4 groups in order to receive the vehicle (saline, control group), magnesium sulfate, melatonin or a combination of magnesium sulfate and melatonin. Treatments were administered intraperitoneally three times; the first being just before ischemia, the second after hypoxia and the third 24 h after the second dose. The pups were sacrificed on postnatal day 10, their brains harvested and evaluated for infarct volume and neuronal apoptosis. RESULTS: Percent infarcted brain volume was significantly reduced in pups receiving the drugs (either magnesium sulfate, melatonin or their combination) compared with those receiving the vehicle. In addition, TUNEL staining showed markedly reduced numbers of TUNEL-positive cells per unit area in the CA1, CA3 and dentate gyrus regions of the hippocampus and in the cortex. However, no statistically significant differences were found regarding percent infarcted brain volume and number of TUNEL-positive cells among the drug-treated groups. CONCLUSIONS: Magnesium sulfate and melatonin, two agents acting at different stages of HI brain damage, administered either alone or in combination, significantly reduced the percent infarcted brain volume and TUNEL positivity, suggesting that these agents may confer a possible benefit in the treatment of infants with HI encephalopathy.


Assuntos
Hipóxia-Isquemia Encefálica/tratamento farmacológico , Sulfato de Magnésio/administração & dosagem , Sulfato de Magnésio/farmacologia , Melatonina/administração & dosagem , Melatonina/farmacologia , Algoritmos , Animais , Animais Recém-Nascidos , Modelos Animais de Doenças , Esquema de Medicação , Combinação de Medicamentos , Avaliação Pré-Clínica de Medicamentos , Feminino , Hipóxia-Isquemia Encefálica/patologia , Fármacos Neuroprotetores/administração & dosagem , Fármacos Neuroprotetores/farmacologia , Gravidez , Ratos , Ratos Sprague-Dawley
11.
Acta Neurochir (Wien) ; 152(6): 1033-42, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20112033

RESUMO

BACKGROUND: Ischemic spinal cord injury is a chain of events caused by the reduction and/or cessation of spinal cord blood flow, which results in neuronal degeneration and loss. Ischemic postconditioning is defined as a series of intermittent interruptions of blood flow in the early phase of reperfusion and has been shown to reduce the infarct size in cerebral ischemia. Our study aimed to characterize the relationship between the neuronal injury-decreasing effects of citicoline and ischemic postconditioning, which were proven to be effective against the apoptotic process. METHOD: Spinal cord ischemia was produced in rats using an intrathoracic approach to implement the synchronous arcus aorta and subclavian artery clipping method. In our study, 42 male Sprague-Dawley rats (309 +/- 27 g) were used. Animals were divided into sham operated, spinal ischemia, citicoline, postconditioning, and postconditioning citicoline groups. Postconditioning was generated by six cycles of 1 min occlusion/5 min reperfusion. A 600 mmol/kg dose of citicoline was given intraperitoneally before ischemia in the citicoline and postconditioning citicoline groups. All rats were sacrificed 96 h after reperfusion. For immunohistochemical analysis, bcl-2, caspase 3, caspase 9, and bax immune staining were performed. Caspase 3, caspase 9, bax, and bcl-2 were used as apoptotic and antiapoptotic markers, respectively. FINDINGS: The blood pressure values obtained at the onset of reperfusion were significantly lower than the preischemic values. A difference in immunohistochemical scoring was detected between the caspase 3, caspase 9, bax, and bcl-2 groups. When comparisons between the ischemia (groups 2, 3, 4, and 5) and sham groups (group 1) were performed, a significant increase in caspase 3, caspase 9, bax, and bcl-2 was detected. When comparing the subgroups, the average score of caspase 9 was found to be significantly higher in ischemia group 2. The average score of bcl-2 was also found to be significantly higher in postconditioning and citicoline group 5. CONCLUSIONS: It is thus thought that combining citicoline with postconditioning provides protection by inhibiting the caspase pathway and by increasing the antiapoptotic proteins.


Assuntos
Citidina Difosfato Colina/farmacologia , Precondicionamento Isquêmico/métodos , Fármacos Neuroprotetores/farmacologia , Nootrópicos/farmacologia , Isquemia do Cordão Espinal/fisiopatologia , 1-Fosfatidilinositol 4-Quinase/metabolismo , Algoritmos , Animais , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Caspase 3/metabolismo , Caspase 9/metabolismo , Ativação Enzimática/fisiologia , Masculino , Neurônios Motores/efeitos dos fármacos , Neurônios Motores/patologia , Neurônios Motores/fisiologia , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/patologia , Traumatismo por Reperfusão/fisiopatologia , Medula Espinal/irrigação sanguínea , Medula Espinal/efeitos dos fármacos , Medula Espinal/patologia , Isquemia do Cordão Espinal/patologia , Proteína X Associada a bcl-2/metabolismo
12.
Turk Neurosurg ; 20(1): 1-8, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20066614

RESUMO

AIM: Apoptosis after cerebral ischemia/reperfusion (I/R) injury leads to the process of cell death. The deal therapeutic approach would target the apoptosis after I/R. Ischemic postconditioning is a recently discovered neuroprotective strategy that involves the application of brief mechanical reperfusion with a specific algorithm at the onset of reperfusion following an ischemic period. MATERIAL AND METHODS: Transient MCAo was performed on male SD (275+/-25 g) rats with intraluminal thread insertion for 2 hrs. Rats (n:36) were treated with postconditioning after 60 minutes of occlusion. The postconditioning algorithm was 30 secs of brief reperfusion followed by 30 secs of MCAo and this cycle was repeated 3 times at the onset of reperfusion. RESULTS: After I/R injury, % change of the malonyldialdehyde (MDA) levels in the cortex, which is an index of lipid peroxidation, was found significantly higher in the I/R group. On the other hand postconditioning upregulated Bcl-2 and Bax translocation to the mitochondria, and caspase-3 activity and also reduced oxidative stress levels. CONCLUSION: These findings indicated this neuroprotective effect is most likely achieved by antiapoptotic mechanisms through caspase pathways.


Assuntos
Apoptose/fisiologia , Isquemia Encefálica/fisiopatologia , Peroxidação de Lipídeos/fisiologia , Traumatismo por Reperfusão/fisiopatologia , Animais , Encéfalo/metabolismo , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patologia , Caspase 3/metabolismo , Lateralidade Funcional , Precondicionamento Isquêmico , Masculino , Mitocôndrias/metabolismo , Fármacos Neuroprotetores , Estresse Oxidativo , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Regulação para Cima , Proteína X Associada a bcl-2/metabolismo
13.
Turk Neurosurg ; 19(4): 406-12, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19847763

RESUMO

Elucidation of the endogenous cell survival pathways involved in ischemic tolerance (preconditioning) and postconditioning has significant clinical implications for preventing neuronal damage in susceptible patients. Ischemic tolerance is a phenomenon in which the brain protects itself against future injury by adapting to low doses of noxious insults. Ischemic postconditioning is defined as brief periods of reperfusion alternating with re-occlusion applied during the very early minutes of reperfusion that mechanically alters the hydrodynamics of reperfusion. Similar pathways and molecules play a role in pre-and postconditioning but their roles and timing are different in each conditioning. Understanding the neuroprotective effects of mechanisms underlying conditioning has been elusive, but NMDA receptor activation, nitric oxide, inflammatory cytokines, and suppression of the innate immune system appear to have a role. Reactive oxygen species and classical ligand stimuli play a role in postconditioning with KATP channels and protein kinase C pathways acting as mediators.


Assuntos
Hipóxia-Isquemia Encefálica/prevenção & controle , Precondicionamento Isquêmico/métodos , Fármacos Neuroprotetores/farmacologia , Animais , Humanos , Hipóxia-Isquemia Encefálica/metabolismo , Hipóxia-Isquemia Encefálica/fisiopatologia
14.
J Clin Neurosci ; 16(5): 693-7, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19268597

RESUMO

We investigated the neuroprotective effects of pre- and postconditioning on infarct volume in the transient middle cerebral artery occlusion (MCAo) model in rats. Thirty-two male rats were divided into occlusion, preconditioning, postconditioning and both pre- and postconditioning groups. MCAo (120 minutes) was monitored with continuous cerebral tissue oxygen (O2) pressure (PtiO2). Pre-conditioning comprised 10 minutes of MCAo, 24 hours prior to the 120 minute MCAo. The postconditioning algorithm was 30 seconds of reperfusion followed by 30 seconds of MCAo. This cycle was repeated 3 times at the onset of reperfusion. Comparison of infarct volumes showed a significant difference between the conditioned groups and occlusion group. Although there was better protection in the preconditioning group compared with the other two conditioned groups, the results did not reach statistically significant levels. The results suggest that preconditioning, postconditioning and pre/post conditioning have protective effects on cerebral ischemia.


Assuntos
Circulação Cerebrovascular/fisiologia , Infarto da Artéria Cerebral Média/prevenção & controle , Precondicionamento Isquêmico/métodos , Reperfusão/métodos , Animais , Modelos Animais de Doenças , Infarto da Artéria Cerebral Média/patologia , Masculino , Exame Neurológico , Oxigênio/metabolismo , Pressão , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão , Estatísticas não Paramétricas , Fatores de Tempo
15.
Turk Neurosurg ; 18(2): 165-71, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18597231

RESUMO

AIM: HI (hypoxic-ischemic) brain injury is a major cause of neonatal mortality and longterm neurological morbidity. The aim of the present study was to investigate the effects of HPC (hypoxic preconditioning) on the oxidative-antioxidative status in the neonatal HI brain model. MATERIAL AND METHODS: Fifty five 7-day-old rats were placed into; Control, HPC, HPC+HI insult, and HI insult groups. HPC, The HPC+HI insult groups were subjected to hypoxia (37 degrees C, 8%O2) and the control group to normoxia for 2.5 hrs. Twenty-four hours later, the rats in the HPC+HI insult and HI insult groups were exposed to cerebral HI produced by unilateral right common carotid artery (CCA) occlusion combined with 90 min hypoxia. Four hours after recovery, the malondialdehyde (MDA) level and the activities of superoxide dismutase (SOD), and glutathione peroxidase (GPx) were determined in the brain tissues of the rats. RESULTS: The findings of the present study suggest increased lipid peroxidation and/or decreased antioxidant activity in the brain of the HI rats. CONCLUSION: The beneficial effects of HPC might not be related to the alterations in the antioxidative activity.


Assuntos
Antioxidantes/metabolismo , Hipóxia-Isquemia Encefálica/metabolismo , Hipóxia-Isquemia Encefálica/fisiopatologia , Precondicionamento Isquêmico , Fatores Etários , Animais , Animais Recém-Nascidos , Encéfalo/enzimologia , Artéria Carótida Primitiva , Modelos Animais de Doenças , Glutationa Peroxidase/metabolismo , Peroxidação de Lipídeos/fisiologia , Malondialdeído/metabolismo , Estresse Oxidativo/fisiologia , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/metabolismo
16.
Surg Neurol ; 64 Suppl 2: S33-41, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16256839

RESUMO

BACKGROUND: Numerous experimental and clinical studies have shown that intrastriatal fetal mesencephalic grafts grow, survive, and reinnervate host brain tissue, resulting in partial recovery of motor deficits. In addition, pharmacological evidence indicates that these grafts increase dopamine secretion in lesioned brain. However, to date, no grafting method has completely restored the nigrostriatal pathway, and there is no consensus on optimal graft numbers or locations. This study compared outcomes with multiple striatal grafts vs a single intranigral graft in a rat model of Parkinson disease. METHODS: Forty-one female Wistar rats weighing 200 to 250 g were used. First, baseline rotational behavior testing with amphetamine injection was done to identify each animal's dominant nigrostriatal pathway (left vs right hemisphere). Some rats then received a unilateral intranigral injection of 6-hydroxydopamine (4 microL [8 microg]) to produce the Parkinson model lesion, and rotational testing was repeated. One group of the lesioned rats received a single intranigral injection of suspended fetal ventral mesencephalic cells (n = 11), and another received multiple intrastriatal grafts of the same type (n = 11). RESULTS: Both grafted groups showed significant improvement on rotational testing with amphetamine and apomorphine at 6 weeks "postgrafting" (P < .001 for "postlesioning" vs postgrafting results in each of the 2 groups); however, the animals with multiple intrastriatal grafts showed complete recovery from motor asymmetry, whereas the rats with single intranigral grafts showed only partial improvement. CONCLUSION: The findings indicate that multiple intrastriatal grafts result in significantly greater functional improvement than single intranigral grafts in this rat Parkinson model.


Assuntos
Transplante de Células/métodos , Corpo Estriado/cirurgia , Transplante de Tecido Fetal/métodos , Mesencéfalo/transplante , Doença de Parkinson/cirurgia , Substância Negra/cirurgia , Adrenérgicos , Animais , Modelos Animais de Doenças , Feminino , Mesencéfalo/citologia , Mesencéfalo/embriologia , Atividade Motora , Oxidopamina , Doença de Parkinson/etiologia , Doença de Parkinson/psicologia , Ratos , Ratos Wistar
17.
Neurosurgery ; 56(2): 382-90; discussion 382-90, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15670386

RESUMO

OBJECTIVE: This study looked at the effects of single and multiple small subarachnoid hemorrhage (SAH) caused by puncturing a small branch of the basilar artery in rats. METHODS: Rats were subjected to single SAH (n = 21), multiple SAH (n = 21), sham operation (n = 21), or no procedures (control group, n = 7). SAH was induced in rats by transclival puncture of a small branch of the basilar artery. In the multiple-SAH hemorrhage groups, three small hemorrhages were produced in the same artery at three different times (initial and 24 and 48 h). In the single-SAH groups, one small hemorrhage was produced. Measurements of local cerebral blood flow (LCBF) were made at the initial SAH procedure and at three different time points. Seven animals from each general grouping were killed on Days 4, 10, and 14 (after LCBF was measured). Three different levels of the basilar artery were examined in each animal. Luminal area and arterial wall thickness were measured, and the findings were compared with control and corresponding sham group findings. RESULTS: LCBF dropped dramatically (by 40%) immediately after SAH and reached levels near baseline within 15 minutes (n = 42) (P < 0.001). LCBF continued to drop after initial SAH and reached the lowest level on Day 10 (P < 0.001) or Day 14 (P < 0.05). Significant luminal narrowing (P < 0.01) and thickening of the arterial wall (P < 0.01) were observed in both groups. CONCLUSION: Single or multiple small SAHs produced by puncturing the basilar artery in the rat cause similar acute and chronic cerebral vasospasm.


Assuntos
Hemorragia Subaracnóidea/complicações , Vasoespasmo Intracraniano/etiologia , Animais , Artéria Basilar/lesões , Doença Crônica , Masculino , Punções , Ratos , Ratos Sprague-Dawley , Hemorragia Subaracnóidea/etiologia
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