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1.
Cell Mol Neurobiol ; 42(3): 739-751, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32918255

RESUMO

Intracerebral hemorrhage (ICH) is a severe stroke subtype caused by the rupture of blood vessels within the brain. Increased levels of S100B protein may contribute to neuroinflammation after ICH through activation of astrocytes and resident microglia, with the consequent production of proinflammatory cytokines and reactive oxygen species (ROS). Inhibition of astrocytic synthesis of S100B by arundic acid (AA) has shown beneficial effects in experimental central nervous system disorders. In present study, we administered AA in a collagenase-induced ICH rodent model in order to evaluate its effects on neurological deficits, S100B levels, astrocytic activation, inflammatory, and oxidative parameters. Rats underwent stereotactic surgery for injection of collagenase in the left striatum and AA (2 µg/µl; weight × 0.005) or vehicle in the left lateral ventricle. Neurological deficits were evaluated by the Ladder rung walking and Grip strength tests. Striatal S100B, astrogliosis, and microglial activation were assessed by immunofluorescence analysis. Striatal levels of interleukin 1ß (IL-1ß) and tumor necrosis factor α (TNF-α) were measured by ELISA, and the ROS production was analyzed by dichlorofluorescein (DCF) oxidation. AA treatment prevented motor dysfunction, reduced S100B levels, astrogliosis, and microglial activation in the damaged striatum, thus decreasing the release of proinflammatory cytokines IL-1ß and TNF-α, as well as ROS production. Taken together, present results suggest that AA could be a pharmacological tool to prevent the harmful effects of increased S100B, attenuating neuroinflammation and secondary brain damage after ICH.


Assuntos
Transtornos Motores , Doenças Neuroinflamatórias , Animais , Caprilatos/farmacologia , Hemorragia Cerebral/complicações , Hemorragia Cerebral/tratamento farmacológico , Hemorragia Cerebral/metabolismo , Microglia/metabolismo , Transtornos Motores/complicações , Ratos
2.
Mol Cell Biochem ; 471(1-2): 63-69, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32472323

RESUMO

Posterior tibial tendon (PTT) dysfunction is three times more common in females, and some patients may have a predisposition without a clinically evident cause, suggesting that individual characteristics play an important role in tendinopathy. The present study investigated the association of rs4986938 (+ 1730G > A; AluI RFLP) and rs1256049 (- 1082G > A; RsaI RFLP) single nucleotide polymorphisms (SNPs) of estrogen receptor-beta (ER-ß) gene with PTT dysfunction. A total of 400 participants were recruited. The PTT dysfunction group: these patients underwent surgery, with PTT tendinopathy confirmed by histopathology and magnetic resonance image (MRI). The control group was composed of participants with no clinical or MRI evidence of PTT dysfunction. Each group was composed of 100 postmenopausal women, 50 premenopausal women, and 50 men. Genomic DNA was extracted from saliva samples, and genotypes were obtained by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP). Concerning the ER-ß SNP rs4986938, there were significant differences in the frequencies of alleles between test and control groups of all the cases, only postmenopausal women and only men (p < 0.0001, p = 0.0016 and p = 0.0001). Considering the PTT dysfunction group and comparing postmenopausal women versus premenopausal women adding men, the analysis showed significant differences in the allelic distribution (p = 0.0450): the allele A in postmenopausal women is a risk factor. The ER-ß SNP rs1256049 did not show differences in the frequencies of alleles and genotypes between groups. The ER-ß SNP rs4986938, but not ER -ß SNPs rs1256049, may contribute to PTT insufficiency in the Brazilian population, with additional risk in postmenopausal women. Addition, in men the genetic factor could be more determinant.


Assuntos
Receptor beta de Estrogênio/genética , Disfunção do Tendão Tibial Posterior/genética , Tendinopatia/genética , Adulto , Alelos , Estudos de Casos e Controles , Estudos Transversais , Feminino , Frequência do Gene , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Fragmento de Restrição , Polimorfismo de Nucleotídeo Único , Disfunção do Tendão Tibial Posterior/patologia , Pós-Menopausa , Tendinopatia/patologia
3.
Neurochem Res ; 44(11): 2631-2642, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31564017

RESUMO

Preterm birth and hypoxia-ischemia (HI) are major causes of neonatal death and neurological disabilities in newborns. The widely used preclinical HI model combines carotid occlusion with hypoxia exposure; however, the relationship between different hypoxia exposure periods with brain tissue loss, astrocyte reactivity and behavioral impairments following HI is lacking. Present study evaluated HI-induced behavioral and morphological consequences in rats exposed to different periods of hypoxia at postnatal day 3. Wistar rats of both sexes were assigned into four groups: control group, HI-120 min, HI-180 min and HI-210 min. Neurodevelopmental reflexes, exploratory abilities and cognitive function were assessed. At adulthood, tissue damage and reactive astrogliosis were measured. Animals exposed to HI-180 and HI-210 min had delayed neurodevelopmental reflexes compared to control group. Histological assessment showed tissue loss that was restricted to the ipsilateral hemisphere in lower periods of hypoxia exposure (120 and 180 min) but affected both hemispheres when 210 min was used. Reactive astrogliosis was increased only after 210 min of hypoxia. Interestingly, cognitive deficits were induced regardless the duration of hypoxia and there were correlations between behavioral parameters and cortex, hippocampus and corpus callosum volumes. These results show the duration of hypoxia has a close relationship with astrocytic response and tissue damage progression. Furthermore, the long-lasting cognitive memory deficit and its association with brain structures beyond the hippocampus suggests that complex anatomical changes should be involved in functional alterations taking place as hypoxia duration is increased, even when the cognitive impairment limit is achieved.


Assuntos
Astrócitos/fisiologia , Hipóxia-Isquemia Encefálica/fisiopatologia , Animais , Animais Recém-Nascidos , Encéfalo/patologia , Disfunção Cognitiva/fisiopatologia , Feminino , Gliose/fisiopatologia , Hipóxia-Isquemia Encefálica/patologia , Masculino , Aprendizagem em Labirinto/fisiologia , Transtornos da Memória/fisiopatologia , Ratos Wistar , Análise de Regressão , Fatores de Tempo
4.
Clin Radiol ; 74(7): 571.e1-571.e8, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31076084

RESUMO

AIM: To evaluate the reliability of ankle syndesmotic measurements and their changes during active motion using four-dimensional computed tomography (4DCT) examination in asymptomatic ankles. MATERIALS AND METHODS: 4DCT was performed on both ankles of patients with signs and symptoms of unilateral ankle instability. Ankles from the asymptomatic side of 10 consecutive patients were included in this analysis. Five ankle syndesmotic measurements were adopted from the available literature and performed by two fellowship-trained foot and ankle surgeons: (1) syndesmotic anterior distance (SAD); (2) syndesmotic posterior distance (SPD); (3) syndesmotic translation (ST); (4) syndesmotic tibiofibular angle (STFA); and (5) ankle tibiofibular angle (ATFA). A Monte Carlo simulation was also performed to obtain exact p-values with 99% confidence intervals. RESULTS: Excellent interobserver reliability was observed among the two readers for four out of five measurements (intra-class correlation coefficients [ICC]: 0.767-0.995, p<0.001-0.020). The ICC values for SAD were not statistically significant (ICC=0.548 and 0.569 for dorsi and plantarflexion respectively, p=0.1). Among the five measurements, only ST measurements had significant changes during active motion (median [interquartile range] for change: -0.70 mm [-1.6-0.10]; p=0.012). Of the above measurements, only the ST measurements demonstrated a negative linear association with the tibiocalcaneal angle during active motion (beta=-2.5, p=0.04). CONCLUSIONS: Reliable quantitative kinematic assessment of ankle syndesmosis can be performed using 4DCT examination. Syndesmotic measurements remain unchanged during ankle motion except for the syndesmotic translation, which tends to decrease during plantar flexion.


Assuntos
Articulação do Tornozelo/diagnóstico por imagem , Articulação do Tornozelo/fisiopatologia , Tomografia Computadorizada Quadridimensional/métodos , Instabilidade Articular/diagnóstico por imagem , Instabilidade Articular/fisiopatologia , Adolescente , Adulto , Fenômenos Biomecânicos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Adulto Jovem
5.
Lasers Med Sci ; 34(4): 659-666, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30250986

RESUMO

The aim of this in vitro study was to analyze the effect of photobiomodulation therapy (PBMT) on the proliferation and undifferentiating status of stem cell from human exfoliated deciduous teeth (SHEDs). PBMT was carried out with an aluminum gallium indium phosphide (InGaAlP) diode laser in contact and punctual mode (continuous wave, 660 nm, 20 mW, 0.028 cm2, and average energy densities of 1 (1 s), 3 (4 s), 5 (7 s), 10 (14 s), 15 (21 s), or 20 (28 s) J/cm2 per point). The immunoprofile of the SHEDs was analyzed using flow cytometry. Cell proliferation was assessed by the MTT reduction assay. Gene expressions of mesenchymal stem cell markers (OCT4, Nestin, CD90, and CD105) were assessed by RT-qPCR 48 h after PBMT. Data were compared by analysis of variance (ANOVA) and Tukey's test (p ≤ 0.05). Cells cultured under nutritional deficit and treated with PBMT at 5 J/cm2 presented similar cell growth than those of positive control group. Cell growth was significantly higher than those of other groups. Mesenchymal stem cell gene markers were still expressed after PBMT at 5 J/cm2. In a short-term analysis, PBMT increases the number of stem cells with no interference in the undifferentiated state of the irradiated cells, which opens wide possibilities for application in tissue regeneration.


Assuntos
Diferenciação Celular/efeitos da radiação , Polpa Dentária/citologia , Terapia com Luz de Baixa Intensidade , Células-Tronco/citologia , Células-Tronco/efeitos da radiação , Proliferação de Células/efeitos da radiação , Células Cultivadas , Regulação da Expressão Gênica/efeitos da radiação , Humanos , Lasers Semicondutores , Fatores de Tempo , Esfoliação de Dente/patologia , Dente Decíduo/citologia
6.
Neurochem Res ; 42(2): 552-562, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27885575

RESUMO

Neonatal hypoxia-ischemia (HI) is an etiologic component of several neurologic pathologies associated to cognitive impairment. The mechanisms involved in HI-induced tissue damage start immediately after HI and extend for days. Acetylcholine is an important neurotransmitter in the central nervous system and exerts a protector effect on tissue damage by modulating inflammation, and cholinesterase inhibitors have shown neuroprotective properties and their action are often attributed to inhibition of the immune response. The administration of Huperzia quadrifariata alkaloid extract (HqAE), with potent and selective cholinesterase inhibitor properties, will reduce the HI induced behavioral deficits and tissue damage. A total of 84 newborn Wistar rat pups at post natal day 7 (PND7) were subjected to right carotid occlusion followed by 1 h of hypoxia (8% of O2) and i.p. injections of saline, vehicle or HqAE (10 mg/kg). Morris Water Maze and inhibitory avoidance tests were used to assess the cognitive function. Flow cytometry was performed at PND11. Histological analysis was performed at PND45. HqAE treatment was able to prevent the HI induced cognitive deficits in both tests and, at PND45, histological analysis showed that HqAE treatment reduced hippocampus tissue damage. Flow cytometry of the injured hippocampus revealed that the treatment was able to reduce cellular death and the number of infiltrating T cells. Altogether, these results show the therapeutic potential of the Huperzia quadrifariata alkaloid extract to prevent cognitive deficits and histological damage caused by neonatal hypoxia-ischemia, probably by reducing cellular death and T cell mobilization.


Assuntos
Alcaloides/uso terapêutico , Inibidores da Colinesterase/uso terapêutico , Huperzia , Hipóxia-Isquemia Encefálica/enzimologia , Fármacos Neuroprotetores/uso terapêutico , Extratos Vegetais/uso terapêutico , Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Animais , Animais Recém-Nascidos , Inibidores da Colinesterase/isolamento & purificação , Inibidores da Colinesterase/farmacologia , Modelos Animais de Doenças , Feminino , Hipóxia-Isquemia Encefálica/prevenção & controle , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Aprendizagem em Labirinto/fisiologia , Fármacos Neuroprotetores/isolamento & purificação , Fármacos Neuroprotetores/farmacologia , Componentes Aéreos da Planta , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Ratos , Ratos Wistar , Resultado do Tratamento
7.
Int Endod J ; 49(9): 858-864, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26281002

RESUMO

AIM: To compare the characteristics of bioceramic endodontic sealer Endosequence BC sealer with those of AH Plus sealer. METHODOLOGY: Cytotoxicity and genotoxicity were analysed on human gingival fibroblasts submitted to cell culture medium conditioned by sealers using the MTT reduction assay and micronucleus formation test (MNT), respectively. Cells grown on fresh medium served as controls. Cell viabilities were measured at 1, 3, 5 and 7 days. The antibacterial activity was analysed on an Enterococcus faecalis strain (ATCC 29212) using both on agar diffusion test (ADT) and a direct contact test (DCT). The inhibition zones in ADT were measured after 48 h and the colony-forming units counting in the DCT after 1, 24, 72 and 168 h. Data were compared by anova and Tukey's test and MNT by Fisher's exact test (P < 0.05). RESULTS: Cultures submitted to Endosequence BC sealer had a significantly higher number of viable cells (P < 0.01) and less micronucleus formation (P < 0.05) than AH Plus sealer. Endosequence BC sealer exhibited significantly smaller inhibition zones (6.00 ± 0.03 mm) than AH Plus sealer (10.31 ± 0.21 mm) (P < 0.05). Moreover, Endosequence BC sealer had significantly smaller antibacterial activity than AH Plus sealer up to 1 h of direct contact (P < 0.05). On other exposure times, both materials had similar antibacterial effectiveness (P > 0.05). CONCLUSIONS: Bioceramic-based sealer had less cytotoxicity and genotoxicity and similar antibacterial effect against E. faecalis in comparison with AH Plus sealer.

8.
Exp Neurol ; 374: 114713, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38325654

RESUMO

There is evidence that maternal milieu and changes in environmental factors during the prenatal period may exert a lasting impact on the brain health of the newborn, even in case of neonatal brain hypoxia-ischemia (HI). The present study aimed to investigate the effects of maternal environmental enrichment (EE) on HI-induced energetic and metabolic failure, along with subsequent neural cell responses in the early postnatal period. Male Wistar pups born to dams exposed to maternal EE or standard conditions (SC) were randomly divided into Sham-SC, HI-SC, Sham-EE, and HI-EE groups. Neonatal HI was induced on postnatal day (PND) 3. The Na+,K+-ATPase activity, mitochondrial function and neuroinflammatory related-proteins were assessed at 24 h and 48 h after HI. MicroPET-FDG scans were used to measure glucose uptake at three time points: 24 h post-HI, PND18, and PND24. Moreover, neuronal preservation and glial cell responses were evaluated at PND18. After HI, animals exposed to maternal EE showed an increase in Na+,K+-ATPase activity, preservation of mitochondrial potential/mass ratio, and a reduction in mitochondrial swelling. Glucose uptake was preserved in HI-EE animals from PND18 onwards. Maternal EE attenuated HI-induced cell degeneration, white matter injury, and reduced astrocyte immunofluorescence. Moreover, the HI-EE group exhibited elevated levels of IL-10 and a reduction in Iba-1 positive cells. Data suggested that the regulation of AKT/ERK1/2 signaling pathways could be involved in the effects of maternal EE. This study evidenced that antenatal environmental stimuli could promote bioenergetic and neural resilience in the offspring against early HI damage, supporting the translational value of pregnancy-focused environmental treatments.


Assuntos
Hipóxia-Isquemia Encefálica , Doenças Neuromusculares , Animais , Ratos , Feminino , Masculino , Gravidez , Animais Recém-Nascidos , Ratos Wistar , Encéfalo/metabolismo , Hipóxia-Isquemia Encefálica/metabolismo , Astrócitos/metabolismo , Glucose/metabolismo , Adenosina Trifosfatases/metabolismo
9.
Neurosci Biobehav Rev ; 145: 105018, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36572200

RESUMO

Sex steroid hormones play an important role in fetal development, brain functioning and neuronal protection. Growing evidence highlights the positive effects of these hormones against brain damage induced by neonatal hypoxia-ischemia (HI). This systematic review with meta-analysis aims to verify the efficacy of sex steroid hormones in preventing HI-induced brain damage in rodent models. The protocol was registered at PROSPERO and a total of 22 articles were included. Moderate to large effects were observed in HI animals treated with sex steroid hormones in reducing cerebral infarction size and cell death, increasing neuronal survival, and mitigating neuroinflammatory responses and astrocyte reactivity. A small effect was evidenced for cognitive function, but no significant effect for motor function; moreover, a high degree of heterogeneity was observed. In summary, data suggest that sex steroid hormones, such as progesterone and 17ß estradiol, improve morphological and cellular outcomes following neonatal HI. Further research is paramount to examine neurological function during HI recovery and standardization of methodological aspects is imperative to reduce the risk of spurious findings.


Assuntos
Hormônios Esteroides Gonadais , Hipóxia-Isquemia Encefálica , Animais , Animais Recém-Nascidos , Encéfalo , Estradiol , Hipóxia-Isquemia Encefálica/tratamento farmacológico , Hipóxia-Isquemia Encefálica/metabolismo , Isquemia , Progesterona/farmacologia , Progesterona/uso terapêutico
10.
Eur J Clin Microbiol Infect Dis ; 31(4): 423-30, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21761126

RESUMO

The purpose of this study was to evaluate the prevalence and clinical risk factors for quinolone resistance (QR) in E. coli strains from males with febrile urinary tract infection (FUTI). An ambispective cross-sectional study was performed in which we evaluated 153 males with a community FUTI caused by E. coli. Among the 153 FUTI episodes, 101 (66%) were due to quinolone susceptible E. coli strains while 52 (34%) were caused by QR E. coli strains. In the univariate analysis QR was associated with older age, higher Charlson scores, dementia, past UTI, urinary tract abnormalities, previous antibiotic use, particularly with fluoroquinolones (FQ), a healthcare-associated (HA)-UTI (HA-UTI) and to four of the components included in the definition of HA-UTI: hospital admission, nursing home residence, indwelling urethral catheter and invasive urinary instrumentation. In the multivariate analysis, HA-UTI (OR 3.82, 95% CI 1.3-11.24; P 0.015) and use of antimicrobials in the previous month (OR 5.82, 95% CI 2.3-14.88; P < 0.001) mainly with FQ (OR 13.97, 95% CI 2.73-71.53; P 0.002) were associated with QR. To have a HA-UTI and a previous use of FQ in the preceding month were strong risk factors for QR E. coli, and thus empirical antimicrobial treatment with quinolones should be avoided in these patients.


Assuntos
Infecções Comunitárias Adquiridas/microbiologia , Farmacorresistência Bacteriana , Infecções por Escherichia coli/microbiologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Quinolonas/farmacologia , Infecções Urinárias/microbiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Infecções Comunitárias Adquiridas/epidemiologia , Estudos Transversais , Infecções por Escherichia coli/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Infecções Urinárias/epidemiologia
11.
Mol Neurobiol ; 59(3): 1970-1991, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35040041

RESUMO

Neonatal hypoxia-ischemia (HI) is a major cause of mortality and morbidity in newborns and, despite recent advances in neonatal intensive care, there is no definitive treatment for this pathology. Once preclinical studies have shown that environmental enrichment (EE) seems to be a promising therapy for children with HI, the present study conducts a systematic review and meta-analysis of articles with EE in HI rodent models focusing on neurodevelopmental reflexes, motor and cognitive function as well as brain damage. The protocol was registered a priori at PROSPERO. The search was conducted in PubMed, Embase and PsycINFO databases, resulting in the inclusion of 22 articles. Interestingly, EE showed a beneficial impact on neurodevelopmental reflexes (SMD= -0.73, CI= [-0.98; -0.47], p< 0.001, I2= 0.0%), motor function (SMD= -0.55, CI= [-0.81; -0.28], p< 0.001, I2= 62.6%), cognitive function (SMD= -0.93, CI= [-1.14; -0.72], p< 0.001, I2= 27.8%) and brain damage (SMD= -0.80, CI= [-1.03; -0.58], p< 0.001, I2= 10.7%). The main factors that potentiate EE positive effects were enhanced study quality, earlier age at injury as well as earlier start and longer duration of EE exposure. Overall, EE was able to counteract the behavioral and histological damage induced by the lesion, being a promising therapeutic strategy for HI.


Assuntos
Hipóxia-Isquemia Encefálica , Animais , Animais Recém-Nascidos , Modelos Animais de Doenças , Meio Ambiente , Hipóxia-Isquemia Encefálica/patologia , Isquemia , Ratos , Ratos Wistar , Roedores
12.
Brain Res ; 1761: 147389, 2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33639200

RESUMO

INTRODUCTION: Cerebral palsy (CP) is the major cause of motor and cognitive impairments during childhood. CP can result from direct or indirect structural injury to the developing brain. In this study, we aimed to describe brain damage and behavioural alterations during early adult life in a CP model using the combination of maternal inflammation, perinatal anoxia and postnatal sensorimotor restriction. METHODS: Pregnant Wistar rats were injected intraperitoneally with 200 µg/kg LPS at embryonic days E18 and E19. Between 3 and 6 h after birth (postnatal day 0 - PND0), pups of both sexes were exposed to anoxia for 20 min. From postnatal day 2 to 21, hindlimbs of animals were immobilized for 16 h daily during their active phase. From PND40, locomotor and cognitive tests were performed using Rota-Rod, Ladder Walking and Morris water Maze. Ex-vivo MRI Diffusion Tensor Imaging (DTI) and Neurite Orientation Dispersion and Density Imaging (NODDI) were used to assess macro and microstructural damage and brain volume alterations induced by the model. Myelination and expression of neuronal, astroglial and microglial markers, as well as apoptotic cell death were evaluated by immunofluorescence. RESULTS: CP animals showed decreased body weight, deficits in gross (rota-rod) and fine (ladder walking) motor tasks compared to Controls. No cognitive impairments were observed. Ex-vivo MRI showed decreased brain volumes and impaired microstructure in the cingulate gyrus and sensory cortex in CP brains. Histological analysis showed increased cell death, astrocytic reactivity and decreased thickness of the corpus callosum and altered myelination in CP animals. Hindlimb primary motor cortex analysis showed increased apoptosis in CP animals. Despite the increase in NeuN and GFAP, no differences between groups were observed as well as no co-localization with the apoptotic marker. However, an increase in Iba-1+ microglia with co-localization to cleaved caspase 3 was observed. CONCLUSION: Our results suggest that experimental CP induces long-term brain microstructural alterations in myelinated structures, cell death in the hindlimb primary motor cortex and locomotor impairments. Such new evidence of brain damage could help to better understand CP pathophysiological mechanisms and guide further research for neuroprotective and neurorehabilitative strategies for CP patients.

13.
Mol Neurobiol ; 58(5): 2297-2308, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33417220

RESUMO

Neonatal hypoxia-ischemia (HI) is among the main causes of mortality and morbidity in newborns. Experimental studies show that the immature rat brain is less susceptible to HI injury, suggesting that changes that occur during the first days of life drastically alter its susceptibility. Among the main developmental changes observed is the mitochondrial function, namely, the tricarboxylic acid (TCA) cycle and respiratory complex (RC) activities. Therefore, in the present study, we investigated the influence of neonatal HI on mitochondrial functions, redox homeostasis, and cell damage at different postnatal ages in the hippocampus of neonate rats. For this purpose, animals were divided into four groups: sham postnatal day 3 (ShP3), HIP3, ShP11, and HIP11. We initially observed increased apoptosis in the HIP11 group only, indicating a higher susceptibility of these animals to brain injury. Mitochondrial damage, as determined by flow cytometry showing mitochondrial swelling and loss of mitochondrial membrane potential, was also demonstrated only in the HIP11 group. This was consistent with the decreased mitochondrial oxygen consumption, reduced TCA cycle enzymes, and RC activities and induction of oxidative stress in this group of animals. Considering that HIP3 and the sham animals showed no alteration of mitochondrial functions, redox homeostasis, and showed no apoptosis, our data suggest an age-dependent vulnerability of the hippocampus to hypoxia-ischemia. The present results highlight age-dependent metabolic differences in the brain of neonate rats submitted to HI indicating that different treatments might be needed for HI newborns with different gestational ages.


Assuntos
Apoptose/fisiologia , Hipocampo/metabolismo , Hipóxia-Isquemia Encefálica/metabolismo , Mitocôndrias/metabolismo , Estresse Oxidativo/fisiologia , Fatores Etários , Animais , Modelos Animais de Doenças , Feminino , Homeostase/fisiologia , Oxirredução , Consumo de Oxigênio/fisiologia , Ratos , Ratos Wistar
14.
Exp Neurol ; 339: 113623, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33529673

RESUMO

Neonatal hypoxia-ischemia (HI) is a major cause of cognitive impairments in infants. Antenatal strategies improving the intrauterine environment can have high impact decreasing pregnancy-derived intercurrences. Physical exercise alters the mother-fetus unity and has been shown to prevent the energetic challenge imposed by HI. This study aimed to reveal neuroprotective mechanisms afforded by pregnancy swimming on early metabolic failure and late cognitive damage, considering animals' sex as a variable. Pregnant Wistar rats were submitted to daily swimming exercise (20' in a tank filled with 32 °C water) during pregnancy. Neonatal HI was performed in male and female pups at postnatal day 7. Electron chain transport, mitochondrial mass and function and ROS formation were assessed in the right brain hemisphere 24 h after HI. From PND45, reference and working spatial memory were tested in the Morris water maze. MicroPET-FDG images were acquired 24 h after injury (PND8) and at PND60, following behavioral analysis. HI induced early energetic failure, decreased enzymatic activity in electron transport chain, increased production of ROS in cortex and hippocampus as well as caused brain glucose metabolism dysfunction and late cognitive impairments. Maternal swimming was able to prevent mitochondrial dysfunction and to improve spatial memory. The intergenerational effects of swimming were sex-specific, since male rats were benefited most. In conclusion, maternal swimming was able to affect the mitochondrial response to HI in the offspring's brains, preserving its function and preventing cognitive damage in a sex-dependent manner, adding relevant information on maternal exercise neuroprotection and highlighting the importance of mitochondria as a therapeutic target for HI neuropathology.


Assuntos
Encéfalo/metabolismo , Hipóxia-Isquemia Encefálica/metabolismo , Hipóxia-Isquemia Encefálica/prevenção & controle , Mitocôndrias/metabolismo , Neuroproteção/fisiologia , Caracteres Sexuais , Natação/fisiologia , Animais , Animais Recém-Nascidos , Encéfalo/patologia , Feminino , Hipóxia-Isquemia Encefálica/patologia , Masculino , Aprendizagem em Labirinto/fisiologia , Mitocôndrias/patologia , Gravidez , Ratos , Ratos Wistar , Fatores de Tempo
15.
Int Endod J ; 43(2): 142-7, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20078703

RESUMO

AIM: To evaluate in a laboratory setting the performance of five methods for the determination of root canal length in primary anterior teeth. METHODOLOGY: Twenty extracted primary incisors, with at least two-thirds of the root, were used. After access cavity preparation, the teeth were embedded in alginate mixed with 0.9% sodium chloride solution. One operator determined root canal length using tactile sense (T), conventional radiography (RAD), tactile sense and conventional radiography (T + RAD), digital radiography (RDIG) and Root ZX electronic apex locator (EAL) methods. Next, the actual length (AL) was visually determined using a K-file from the coronal reference to the apical foramen or apical resorption level. The measurements obtained through each method were compared to the AL using the intraclass correlation coefficient (ICC) with the limits of agreement calculated with Bland and Altman analysis. The measurements were classified as acceptable (+/-1 mm from the AL) or not (>1 mm shorter or longer), and the McNemar test was employed for method comparison. RESULTS: Differences, limits of agreement and ICCs for each method were respectively EAL = -0.29; -1.02 to 0.44; 0.990; T + RAD = 0.17; -2.18 to 2.51; 0.929; RAD = 0.50; -3.41 to 4.41; 0.818; RDIG = 0.95; -3.76 to 5.65; 0.700; and T = -0.48; -5.59 to 4.64; 0.499. The most accurate and acceptable method was the EAL, followed by the T + RAD. : The EAL method performed best for root canal length determination in primary teeth.


Assuntos
Incisivo/anatomia & histologia , Tratamento do Canal Radicular/instrumentação , Ápice Dentário/anatomia & histologia , Dente Decíduo/anatomia & histologia , Instrumentos Odontológicos , Cavidade Pulpar/anatomia & histologia , Cavidade Pulpar/diagnóstico por imagem , Humanos , Incisivo/diagnóstico por imagem , Odontometria/instrumentação , Radiografia Dentária , Radiografia Dentária Digital , Reprodutibilidade dos Testes , Ápice Dentário/diagnóstico por imagem , Dente Decíduo/diagnóstico por imagem
16.
Brain Res ; 1728: 146592, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31816318

RESUMO

In the last decade, increased homocysteine levels have been implicated as a risk factor for neurodegenerative and psychiatric disorders. We have developed an experimental model of chronic mild hyperhomocysteinemia (HHcy) in order to observe metabolic impairments in the brain of adult rodents. Besides its known effects on brain metabolism, the present study sought to investigate whether chronic mild HHcy could induce learning/memory impairments associated with biochemical and histological damage to the hippocampus. Adult male Wistar rats received daily subcutaneous injections of homocysteine (0.03 µmol/g of body weight) twice a day, from the 30th to the 60th day of life or saline solution (Controls). After injections, anxiety-like and memory tests were performed. Following behavioral analyses, brains were sliced and hippocampal volumes assessed and homogenized for redox state assessment, antioxidant activity, mitochondrial functioning (chain respiratory enzymes and ATP levels) and DNA damage analyses. Behavioral analyses showed that chronic mild HHcy may induce anxiety-like behavior and impair long-term aversive memory (24 h) that was evaluated by inhibitory avoidance task. Mild HHcy decreased locomotor and/or exploratory activities in elevated plus maze test and caused hippocampal atrophy. Decrease in cytochrome c oxidase, DNA damage and redox state changes were also observed in hippocampus of adult rats subjected to mild HHcy. Our findings show that chronic mild HHcy alters biochemical and histological parameters in the hippocampus, leading to behavioral impairments. These findings might be considered in future studies aiming to search for alternative strategies for treating the behavioral impairments in patients with mild elevations in homocysteine levels.


Assuntos
Ansiedade/etiologia , Hipocampo/patologia , Hiper-Homocisteinemia/complicações , Transtornos da Memória/etiologia , Trifosfato de Adenosina/metabolismo , Animais , Ansiedade/patologia , Atrofia/etiologia , Atrofia/patologia , Aprendizagem da Esquiva , Doença Crônica , Dano ao DNA/fisiologia , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Hipocampo/fisiopatologia , Homocisteína/sangue , Hiper-Homocisteinemia/induzido quimicamente , Masculino , Transtornos da Memória/fisiopatologia , Teste de Campo Aberto , Estresse Oxidativo/fisiologia , Ratos , Ratos Wistar
17.
Neuroscience ; 440: 97-112, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32474054

RESUMO

Stroke is one of the leading causes of mortality and neurological morbidity. Intracerebral hemorrhage (ICH) has the poorest prognosis among all stroke subtypes and no treatment has been effective in improving outcomes. Following ICH, the observed high levels of S100B protein have been associated with worsening of injury and neurological deficits. Arundic acid (AA) exerts neuroprotective effects through inhibition of astrocytic synthesis of S100B in some models of experimental brain injury; however, it has not been studied in ICH. The aim of this study was to evaluate the effects of intracerebroventricular (ICV) administration of AA in male Wistar rats submitted to ICH model assessing the following variables: reactive astrogliosis, S100B levels, antioxidant defenses, cell death, lesion extension and neurological function. Firstly, AA was injected at different doses (0.02, 0.2, 2 and 20 µg/µl) in the left lateral ventricle in order to observe which dose would decrease GFAP and S100B striatal levels in non-injured rats. Following determination of the effective dose, ICH damage was induced by IV-S collagenase intrastrial injection and 2 µg/µl AA was injected through ICV route immediately before injury. AA treatment prevented ICH-induced neurological deficits and tissue damage, inhibited excessive astrocytic activation and cellular apoptosis, reduced peripheral and central S100B levels (in striatum, serum and cerebrospinal fluid), improved neuronal survival and enhanced the antioxidant defences after injury. Altogether, these results suggest that S100B is a viable target for treating ICH and highlight AA as an interesting strategy for improving neurological outcome after experimental brain hemorrhage.


Assuntos
Lesões Encefálicas , Fármacos Neuroprotetores , Animais , Caprilatos , Hemorragia Cerebral/complicações , Hemorragia Cerebral/tratamento farmacológico , Modelos Animais de Doenças , Masculino , Fármacos Neuroprotetores/farmacologia , Ratos , Ratos Wistar , Subunidade beta da Proteína Ligante de Cálcio S100
18.
Brain Res ; 1733: 146722, 2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-32045594

RESUMO

Neonatal hypoxia-ischemia (HI) is one of the main causes of neurological damage in newborns. Pregnancy swimming (PS) alters brain maturation and has neuroprotective effects following HI; however, variables such as timing play a decisive role in its effects. Prior to mating, we tested if adaptation of female rats to a tank filled with water at 32 °C for 7 days before mating, modulates PS benefits. After mating, rats swam 20 min/day or remained in standard cages. Seven-day-old pups were subjected to HI (right common carotid artery occlusion followed by FiO2 8% for 60 min). Animals were divided into 8 experimental groups, adaptation, swimming and injury. Astrocytic reactivity, apoptosis-related proteins, neurotrophins and cell survival markers expression were assessed in the hippocampus 24 h after HI. From PND45, animals performed behavioral tests followed by histological assessment. Three-way ANOVA showed a significant increase in astrogliosis only in non-adapted HI animals. Swimming decreased apoptotic cell death despite adaptation period in both exercised groups. Cylinder evidenced HI impairments; no effect of swimming or adaptation period were observed. In the open field, only HI animals whose mothers had been adapted had increased locomotion; moreover, swimming reversed HI damage. Hemisphere and hippocampus were preserved only in the HI group whose mothers swam before mating, suggesting a preconditioning effect mediated by the adaptation. In summary, adaptation period plays a major role in the mechanisms involving neuroprotection afforded by PS and needs to be further explored in future studies involving damage to the neonatal brain.


Assuntos
Adaptação Fisiológica , Hipocampo/metabolismo , Hipóxia-Isquemia Encefálica/metabolismo , Neuroproteção , Natação , Animais , Animais Recém-Nascidos , Comportamento Animal , Feminino , Hipóxia-Isquemia Encefálica/prevenção & controle , Gravidez , Ratos Wistar
19.
Exp Neurol ; 330: 113317, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32304750

RESUMO

Neonatal hypoxia ischemia (HI) is the main cause of newborn mortality and morbidity. Preclinical studies have shown that the immature rat brain is more resilient to HI injury, suggesting innate mechanisms of neuroprotection. During neonatal period brain metabolism experience changes that might greatly affect the outcome of HI injury. Therefore, the aim of the present study was to investigate how changes in brain metabolism interfere with HI outcome in different stages of CNS development. For this purpose, animals were divided into 6 groups: HIP3, HIP7 and HIP11 (HI performed at postnatal days 3, 7 and 11, respectively), and their respective shams. In vivo [18F]FDG micro positron emission tomography (microPET) imaging was performed 24 and 72 h after HI, as well as ex-vivo assessments of glucose and beta-hydroxybutyrate (BHB) oxidation. At adulthood behavioral tests and histology were performed. Behavioral and histological analysis showed greater impairments in HIP11 animals, while HIP3 rats were not affected. Changes in [18F]FDG metabolism were found only in the lesion area of HIP11, where a substantial hypometabolism was detected. Furthermore, [18F]FDG hypometabolism predicted impaired cognition and worst histological outcomes at adulthood. Finally, substrate oxidation assessments showed that glucose oxidation remained unaltered and higher level of BHB oxidation found in P3 animals, suggesting a more resilient metabolism. Overall, present results show [18F]FDG microPET predicts long-term injury outcome and suggests that higher BHB utilization is one of the mechanisms that confer the intrinsic neuroprotection to the immature brain and should be explored as a therapeutic target for treatment of HI.


Assuntos
Ácido 3-Hidroxibutírico/metabolismo , Glucose/metabolismo , Hipóxia-Isquemia Encefálica/metabolismo , Neuroproteção/fisiologia , Animais , Animais Recém-Nascidos , Modelos Animais de Doenças , Masculino , Ratos , Ratos Wistar
20.
Med Intensiva (Engl Ed) ; 44(1): 36-45, 2020.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-31542182

RESUMO

Sepsis is a syndromic entity with high prevalence and mortality. The management of sepsis is standardized and exhibits time-dependent efficiency. However, the management of patients with sepsis is complex. The heterogeneity of the forms of presentation can make it difficult to detect and manage such cases, in the same way as differences in training, professional competences or the availability of health resources. The Advisory Commission for Patient Care with Sepsis (CAAPAS), comprising 7 scientific societies, the Emergency Medical System (SEM) and the Catalan Health Service (CatSalut), have developed the Interhospital Sepsis Code (CSI) in Catalonia (Spain). The general objective of the CSI is to increase awareness, promote early detection and facilitate initial care and interhospital coordination to attend septic patients in a homogeneous manner throughout Catalonia.


Assuntos
Comitês Consultivos/organização & administração , Codificação Clínica/normas , Sepse/diagnóstico , Sepse/terapia , Fatores Etários , Algoritmos , Circulação Sanguínea , Codificação Clínica/organização & administração , Diagnóstico Precoce , Emergências , Hospitais/normas , Humanos , Anamnese , Meningismo/diagnóstico , Modelos Organizacionais , Insuficiência de Múltiplos Órgãos/diagnóstico , Exame Físico , Síndrome do Desconforto Respiratório/diagnóstico , Ressuscitação/normas , Sepse/sangue , Choque Séptico/sangue , Choque Séptico/diagnóstico , Choque Séptico/terapia , Espanha/epidemiologia , Inconsciência/diagnóstico
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