Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 68
Filtrar
1.
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
2.
Sci Rep ; 11(1): 2224, 2021 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-33500453

RESUMO

Phylogenetic analysis has demonstrated that the etiologic agent of the 2020 pandemic outbreak is a betacoronavirus named SARS-CoV-2. For public health interventions, a diagnostic test with high sensitivity and specificity is required. The gold standard protocol for diagnosis by the Word Health Organization (WHO) is RT-PCR. To detect low viral loads and perform large-scale screening, a low-cost diagnostic test is necessary. Here, we developed a cost-effective test capable of detecting SARS-CoV-2. We validated an auxiliary protocol for molecular diagnosis with the SYBR Green RT-PCR methodology to successfully screen negative cases of SARS-CoV-2. Our results revealed a set of primers with high specificity and no homology with other viruses from the Coronovideae family or human respiratory tract pathogenic viruses, presenting with complementarity only for rhinoviruses/enteroviruses and Legionella spp. Optimization of the annealing temperature and polymerization time led to a high specificity in the PCR products. We have developed a more affordable and swift methodology for negative SARS-CoV-2 screening. This methodology can be applied on a large scale to soften panic and economic burden through guidance for isolation strategies.


Assuntos
Teste de Ácido Nucleico para COVID-19/métodos , COVID-19/diagnóstico , Compostos Orgânicos , Reação em Cadeia da Polimerase em Tempo Real/métodos , SARS-CoV-2 , Benzotiazóis , DNA de Cadeia Simples , Diaminas , Enterovirus , Genoma Viral , Humanos , Filogenia , Reação em Cadeia da Polimerase , Quinolinas , Rhinovirus , Sensibilidade e Especificidade , Temperatura , Carga Viral
3.
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
4.
Int J Dev Neurosci ; 69: 112-118, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30048676

RESUMO

Focal Cortical Dysplasia (FCD), a common type of Malformations of cortical development, may result from an early disturbance in the migration and final arrangement of the cortical architecture of immature neurons. FCD type II is now known to be due to a post-zygotic somatic mutation that involves the mTOR and AKT pathways. The aim of the present study was to investigate the possible differences in neurogenesis and neurodifferentiation of iPSCs (induced pluripotent stem cells) from fibroblasts of individuals affected by FCD type II (2) and normal individuals (2). iPSCs were generated from skin fibroblasts of FCD individuals and healthy individuals. The reprogramming was done through the fibroblasts exposure to viral vectors containing the OCT4, KLF4, SOX2, and c-MYC genes and the clones were characterized by immunohistochemistry. iPSCs were neurodifferentiated and analyzed at the 14th, 22nd and 35th days. We also analyzed the cerebral cortex tissue, fibroblasts and iPSCs cells from the individuals. Through qRT-PCR, the expression of 4 genes involved in Notch signaling process were quantified. In general, individuals with dysplasia presented increase and decrease in the relative quantification in the most genes analyzed compared to control individuals in all processes and study groups. We suggest that, during embryonic neurogenesis, the neural precursor cells of FCD type II individuals present increase and decrease in gene expression in the Notch signaling pathway causing cortical formation disorders and can be seen as a candidate for the developmental changes observed in the cerebral cortex of individuals with FCD type II. This altered gene expression may be related to brain formation with dysplasia.


Assuntos
Epilepsia/genética , Epilepsia/metabolismo , Malformações do Desenvolvimento Cortical do Grupo I/genética , Malformações do Desenvolvimento Cortical do Grupo I/metabolismo , Células-Tronco Neurais/metabolismo , Células-Tronco Pluripotentes/metabolismo , Receptores Notch/metabolismo , Transdução de Sinais/genética , Córtex Cerebral/citologia , Criança , Potenciais Pós-Sinápticos Excitadores/genética , Feminino , Fibroblastos , Regulação da Expressão Gênica , Voluntários Saudáveis , Humanos , Imuno-Histoquímica , Fator 4 Semelhante a Kruppel , Masculino , Pessoa de Meia-Idade , Neurogênese/genética , Pele/citologia
5.
Spinal Cord Ser Cases ; 2: 15001, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28053726

RESUMO

INTRODUCTION: Posterior reversible encephalopathy syndrome (PRES) is an entity characterized by neurologic symptoms such as headaches, altered mental status, seizures and visual changes, and it is associated with white matter vasogenic edema predominantly affecting the posterior occipital and parietal lobes of the brain. CASE REPORT: A 19-year-old patient developed PRES after the use of chemotherapy for a testicular teratocarcinoma and after the development of a blood pressure elevation. DISCUSSION: Few cases described the involvement of the spinal cord in this syndrome. In the majority of these cases, the spinal cord involvement was asymptomatic or with few symptoms of spinal cord disease.

6.
Phys Chem Chem Phys ; 14(25): 9104-11, 2012 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-22644312

RESUMO

The combined effect of minor yttrium doping and silver catalyst deposition on the surface kinetics (k(chem)) and bulk diffusion (D(chem)) of BSCF (Ba(0.5)Sr(0.5)Co(0.8)Fe(0.2)O(3-δ)) perovskite membranes was explored using electrical conductivity relaxation (ECR) and validated using oxygen permeation measurements. Yttrium doping of BSCF to form Ba(0.5)Sr(0.5)Co(0.8)Fe(0.175)Y(0.025)O(3-δ) (BSCFY) improved both the surface exchange kinetics and the bulk diffusion by an average of 44% and 177% respectively, supporting improved oxygen permeation measurements. The deposition of a silver catalyst on BSCFY further improved the surface kinetics by 63-450% at intermediate operating temperatures (600-750 °C), and reduced the activation energy from 163 to 90 kJ mol(-1). Interestingly, these improvements did not translate into enhanced oxygen fluxes for the silver coated thicker 0.5 and 1 mm membranes, indicating that the oxygen ion transport was limited by bulk diffusion. However, oxygen permeation measurements on catalyst-coated 0.3 mm-thick membranes yielded improvements of 20-35% in the range 600-900 °C. The silver catalyst was beneficial in overcoming surface kinetic limitations for the thinner 0.3 mm BSCFY membranes, thus suggesting that the critical thickness of BSCFY membranes lies around ∼0.4 mm and validating the ECR measurements.

7.
J Colloid Interface Sci ; 314(2): 589-603, 2007 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-17588594

RESUMO

Hydrogen as a high-quality and clean energy carrier has attracted renewed and ever-increasing attention around the world in recent years, mainly due to developments in fuel cells and environmental pressures including climate change issues. In thermochemical processes for hydrogen production from fossil fuels, separation and purification is a critical technology. Where water-gas shift reaction is involved for converting the carbon monoxide to hydrogen, membrane reactors show great promises for shifting the equilibrium. Membranes are also important to the subsequent purification of hydrogen. For hydrogen production and purification, there are generally two classes of membranes both being inorganic: dense phase metal and metal alloys, and porous ceramic membranes. Porous ceramic membranes are normally prepared by sol-gel or hydrothermal methods, and have high stability and durability in high temperature, harsh impurity and hydrothermal environments. In particular, microporous membranes show promises in water gas shift reaction at higher temperatures. In this article, we review the recent advances in both dense phase metal and porous ceramic membranes, and compare their separation properties and performance in membrane reactor systems. The preparation, characterization and permeation of the various membranes will be presented and discussed. We also aim to examine the critical issues in these membranes with respect to the technical and economical advantages and disadvantages. Discussions will also be made on the relevance and importance of membrane technology to the new generation of zero-emission power technologies.

8.
Water Res ; 41(17): 3998-4004, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17583764

RESUMO

The supply security of fresh drinking water is decreasing and raising a critical situation for communities worldwide. Inorganic membranes such as alumina and molecular sieve silica have in the past been shown to be highly effective at separating gases and could offer promise as liquid separators due to their high flux and stability. In this work, we develop a range of inorganic membranes with pore size ranging from 0.3 to 500nm and relate this to separation and transport performance. Best separation results were achieved for the silica membrane pressurised to only 7bar, exhibiting a flux of around 1.8kgm(-2)h(-1) and NaCl rejection of 98% with 3.5wt% (seawater-like) feed. Potable water from seawater-like feed was achieved from the membrane in a single stage after regeneration. Conditions such as pressure and temperature were also modified showing performance characteristics and diffusion mechanisms. The non-osmotic set-up for inorganic membranes is therefore a viable technology for desalination.


Assuntos
Membranas Artificiais , Cloreto de Sódio/isolamento & purificação , Purificação da Água/métodos , Óxido de Alumínio/química , Osmose , Porosidade , Pressão , Dióxido de Silício/química , Temperatura , Fatores de Tempo , Volatilização , Abastecimento de Água
9.
J Nanosci Nanotechnol ; 4(3): 265-9, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15233087

RESUMO

High-quality nanometer thick ultramicroporous membranes were prepared from silica sol-gel processes and tested for the permeation of binary gas mixtures of He, H2, CO2, and CH4 across different temperature and partial pressure regimens. Pore size distribution by molecular probing showed that the majority of pore sizes had dimensions below 2.9 A. In 50:50 binary mixtures, the fluxes of gases increased as a function of temperature, indicating an activated transport mechanism. The ultramicroporous membranes showed high selectivities at 150 degrees C for He/CO2 (30), He/CH4 (93), H2/CO2 (10), and H2/CH4 (9) with lower selectivities for CO2/CH4 (5). High activation energies (Ea) were observed for the permeance of 50:50 binary mixtures containing He and H2 of 22.1-27.5 and 17.6-23.1 kJ.mol-1, respectively. The Ea for the permeance of the total mixture approached the Ea for the permeance of the molecule with the smaller kinetic diameter (He or H2).


Assuntos
Dióxido de Carbono/química , Misturas Complexas/química , Hélio/química , Hidrogênio/química , Membranas Artificiais , Metano/química , Nanotecnologia/métodos , Ultrafiltração/métodos , Dióxido de Carbono/isolamento & purificação , Misturas Complexas/isolamento & purificação , Gases/análise , Gases/química , Hélio/isolamento & purificação , Hidrogênio/isolamento & purificação , Teste de Materiais , Metano/isolamento & purificação , Nanotecnologia/instrumentação , Permeabilidade , Porosidade , Temperatura , Ultrafiltração/instrumentação
10.
J Nanosci Nanotechnol ; 4(3): 270-4, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15233088

RESUMO

This article reports a study of the effects of synthesis parameters on the preparation and formation of mesoporous titania nanopowders by employing a two-step sol-gel method. These materials displayed crystalline domains characteristic of anatase. The first step of the process involved the hydrolysis of titanium isopropoxide in a basic aqueous solution mediated by neutral surfactant. The solid product obtained from step 1 was then treated in an acidified ethanol solution containing the same titanium precursor to thicken the pore walls. Low pH and higher loading of the Ti precursor in step 2 produced better mesoporosity and crystallinity of titanium dioxide polymorphs. The resultant powder exhibited a high surface area (73.8 m2/g) and large pore volume (0.17 cm3/g) with uniform mesopores. These materials are envisaged to be used as precursors for mesoporous titania films as a wide band gap semiconductor in dye-sensitized nanocrystalline TiO2 solar cells.


Assuntos
Cristalização/métodos , Teste de Materiais , Nanotecnologia/métodos , Titânio/química , Manufaturas/análise , Conformação Molecular , Transição de Fase , Porosidade , Propriedades de Superfície , Titânio/análise
11.
Clin Rheumatol ; 21(1): 32-4, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11954881

RESUMO

With the aim of clarifying whether patient age could be an additional explanation for the differences in the clinical expression of rheumatoid arthritis (RA) found in different populations, we evaluated the possibility of patient age being a significant factor associated with global functional status, independent from disease duration. Our present results suggest that both disease duration and patient age are major factors in the global functional status of patients with RA, and that patient age is particularly important when a subgroup of patients with more than 60 years of age and more than 20 years of disease duration is considered. These data are relevant when comparing two different RA groups: not only should we have a similar mean age and mean disease duration, but also the subgroups of patients more than 60 years of age and with more than 20 years of disease duration should correspond to equivalent proportions in the populations studied.


Assuntos
Envelhecimento/fisiologia , Artrite Reumatoide/fisiopatologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Fatores de Tempo
12.
Epilepsia ; 42(9): 1124-9, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11580758

RESUMO

PURPOSE: To analyze the results of surgical treatment of intractable epilepsy in patients with subcortical band heterotopia, or double cortex syndrome, a diffuse neuronal migration disorder. METHODS: We studied eight patients (five women) with double cortex syndrome and intractable epilepsy. All had a comprehensive presurgical evaluation including prolonged video-EEG recordings and magnetic resonance imaging (MRI). RESULTS: All patients had partial seizures, with secondary generalization in six of them. Neurologic examination was normal in all. Three were of normal intelligence, and five were mildly retarded. Six patients underwent invasive EEG recordings, three of them with subdural grids and three with stereotactic implanted depth electrodes (SEEG). Although EEG recordings showed multilobar epileptic abnormalities in most patients, regional or focal seizure onset was recorded in all. MRI showed bilateral subcortical band heterotopia, asymmetric in thickness in three. An additional area of cortical thickening in the left frontal lobe was found in one patient. Surgical procedures included multiple subpial transections in two patients, frontal lesionectomy in one, temporal lobectomy with amygdalohippocampectomy in five, and an additional anterior callosotomy in one. Five patients had no significant improvement, two had some improvement, and one was greatly improved. CONCLUSION: Our results do not support focal surgical removal of epileptogenic tissue in patients with double cortex syndrome, even in the presence of a relatively localized epileptogenic area.


Assuntos
Córtex Cerebral/anormalidades , Córtex Cerebral/cirurgia , Epilepsia/cirurgia , Adolescente , Adulto , Criança , Corpo Caloso/cirurgia , Eletroencefalografia/estatística & dados numéricos , Epilepsias Parciais/diagnóstico , Epilepsias Parciais/etiologia , Epilepsias Parciais/cirurgia , Epilepsia/diagnóstico , Epilepsia/etiologia , Epilepsia Parcial Complexa/diagnóstico , Epilepsia Parcial Complexa/etiologia , Epilepsia Parcial Complexa/cirurgia , Epilepsia do Lobo Temporal/diagnóstico , Epilepsia do Lobo Temporal/etiologia , Epilepsia do Lobo Temporal/cirurgia , Feminino , Seguimentos , Humanos , Masculino , Malformações do Sistema Nervoso/complicações , Malformações do Sistema Nervoso/diagnóstico , Malformações do Sistema Nervoso/cirurgia , Síndrome , Resultado do Tratamento
14.
Int J Obes Relat Metab Disord ; 25(1): 24-32, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11244454

RESUMO

OBJECTIVE: To relate psychological profiles, cerebral asymmetry and the hypothalamus-pituitary-adrenal axis (HPA) reactivity to clinical characteristics of common obesity. METHODS: Sixty consecutive adult female overweight and obese patients attending the outpatient endocrine department were included in this study. Clinical evaluation specifically selected a priori the following indexes: obesity age of onset, parenthood obesity, carbohydrate craving, binge eating with purging, obesity degree (defined by the body mass index (BMI)--weight (kg)/height (m(2))), body fat distribution (defined by the abdominal--thigh ratio (A/T)) and initial weight loss after medical treatment. Psychological evaluation was performed with the Minnesota Multiphasic Personality Inventory (MMPI). In the last 30 patients, the Edinburgh Inventory of Manual Preference (EIMP) and the corticotrophin-releasing hormone (CRH) test were also performed. RESULTS: Clinical characteristics defined a priori were independent variables as evaluated by contingency table analysis. Factorial analysis of variance (ANOVA) revealed a significantly different MMPI profile, according to parental obesity, with post-hoc significantly higher scores on the hypochondriasis (Hs), paranoia (Pa), psychasthenia (Pt) and schizophrenia (Sc) scales in patients with obese parents. Obese patients presented significantly higher dichotomized manual preference indexes in relation to overweight patients. Parental obesity, binge eating behaviour with purging, body fat distribution and the dichotomized manual preference index were independent significant factors for the ACTH response in the CRH test, together explaining 41% of the response variability. Age of onset of obesity and the dichotomized manual preference index were independent and significant factors for the cortisol response, together explaining 37% of its variability. A non-normal distribution was found for the ACTH response: high- and low-responders presented significantly different MMPI profiles, with high-responders presenting higher scores on all clinical scales except masculinity/femininity (Mf). CONCLUSION: Overweight/obese subjects with parental obesity present a distinctive personality profile and a higher ACTH response in the CRH test. Cerebral asymmetry may be a relevant factor for obesity development and is associated with the HPA reactivity. HPA reactivity is a sensitive index integrating clinical, psychological and neural asymmetric factors. International Journal of Obesity (2001) 25, 24-32


Assuntos
Sistema Hipotálamo-Hipofisário/fisiopatologia , MMPI , Obesidade/psicologia , Sistema Hipófise-Suprarrenal/fisiopatologia , Tecido Adiposo/anatomia & histologia , Hormônio Adrenocorticotrópico/sangue , Adulto , Idade de Início , Análise de Variância , Constituição Corporal/fisiologia , Índice de Massa Corporal , Estudos de Casos e Controles , Hormônio Liberador da Corticotropina , Transtornos da Alimentação e da Ingestão de Alimentos/fisiopatologia , Transtornos da Alimentação e da Ingestão de Alimentos/psicologia , Feminino , Lateralidade Funcional , Humanos , Hidrocortisona/sangue , Cinética , Obesidade/classificação , Obesidade/fisiopatologia
15.
J Nanosci Nanotechnol ; 1(3): 331-6, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12914071

RESUMO

Silica xerogels were prepared by a sol-gel process catalyzed by acid with tetraethylorthosilicate, and using an organic covalent ligand template (methyltriethoxysilane) or a noncovalent template C6 surfactant (triethylhexylammonium bromide). The influence of hydrotreatment on the structure of templated xerogels is examined in terms of surface area, micropore volume, average pore size, and pore size distribution, and compared against a blank xerogel (nontemplated). The role of surface functional groups was evaluated using 29Si nuclear magnetic resonance. The structural integrity of the xerogel was maintained to a large extent in samples that had a high contribution of Q4 species (siloxane groups). Xerogel matrix densification occurred when there was a large concentration of Q3 and Q2 species (silanol groups), which also were responsible for increased hydrophilicity. The templated xerogels resulted in up to a 25% concentration of methyl functional groups (T3 and T2 species), leading to hydrophobic xerogels. The best results in terms of structural integrity and hydrophobicity were obtained with templated xerogels prepared with the C6 surfactant. The results in this study suggest that surfactant-enhanced condensation reactions lead to structures with a high contribution of Q4 groups, which are not susceptible to water attack, but are strong enough to oppose matrix densification during rehydration.


Assuntos
Filtros Microporos , Nanotecnologia/métodos , Dióxido de Silício/química , Ultrafiltração/instrumentação , Ultrafiltração/métodos , Água/química , Adsorção , Interações Hidrofóbicas e Hidrofílicas , Substâncias Macromoleculares , Microquímica/métodos , Conformação Molecular , Nitrogênio/química , Porosidade , Sílica Gel , Dióxido de Silício/classificação , Dióxido de Silício/isolamento & purificação , Temperatura
16.
Clin Exp Rheumatol ; 18(5): 559-64, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11072594

RESUMO

OBJECTIVE: Routine histologic techniques are still the main procedure in the study of the synovial biopsy. The relationship between the typical histological changes of rheumatoid synovium and clinical manifestations has not been studied in detail. METHODS: With the aim of determining whether a simple semiquantitative method of evaluating the changes in closed synovial biopsies was of clinical value in assessing both the diagnosis and prognosis of rheumatoid arthritis (RA) patients, we evaluated retrospectively 72 synovial biopsy specimens (26 RA patients, 30 patients with other inflammatory diseases and 16 osteoarthritis patients). Scores (0-10) were assigned to each biopsy specimen for each of 6 histologic features: synoviocyte hyperplasia; fibrosis in the subsynovial layer; proliferating blood vessels; perivascular infiltrates of lymphocytes; focal aggregates of lymphocytes; and diffuse infiltrates of lymphocytes. Scores were compared between the 3 groups and also between the RA subgroups with early and late disease; positive and negative rheumatoid factor; with and without joint erosions; and with and without systemic disease. RESULTS: Significant differences in the mean global score (mean of the 6 scores) were found both between RA and osteoarthritis and between other inflammatory diseases and osteoarthritis (p < 0.01). The mean global score for RA was higher than the mean global score obtained for the other inflammatory diseases, but the difference was not significant. We found a significantly higher mean global score in the RA patients with erosions in comparison to the RA patients without erosions, this difference being particularly evident for the lymphocyte perivascular infiltrate (p < 0.05). There were no significant differences between the other RA subgroups. CONCLUSION: In this study we have identified differences, using routine histologic techniques, between the rheumatoid synovial membrane of patients with and without erosions. Based on our present observations we suggest that the intensity of inflammatory histological features and, in particular, a high percentage of vessels with perivascular lymphocyte infiltrate might be of prognostic value in RA.


Assuntos
Artrite Reumatoide/patologia , Articulações/patologia , Membrana Sinovial/patologia , Idoso , Feminino , História do Século XVI , Humanos , Inflamação/patologia , Masculino , Pessoa de Meia-Idade , Osteoartrite/patologia , Prognóstico , Estudos Retrospectivos , Método Simples-Cego
17.
Clin Neurophysiol ; 111 Suppl 2: S74-80, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10996558

RESUMO

Seizures are one of the most frequent problems in the neonatal period, and are frequently associated with high mortality and morbidity rates. On the other hand, neonatal seizures may represent a first or even the only sign of central nervous system dysfunction. However, establishing the diagnosis of neonatal seizures poses several problems, and clinical observation is not sufficient in many cases. Neonatal polysomnography is a valuable tool both in the diagnostic and in the prognostic assessment of neonatal seizures. The present text reviews some technical aspects related to neonatal polysomnographies, and its usefulness in the area of suspected neonatal seizures. Moreover, some questions are raised regarding rhythmic discharges and their significance as a possible ictal and interictal epileptic pattern in the neonate.


Assuntos
Encéfalo/fisiopatologia , Epilepsia/fisiopatologia , Polissonografia , Eletroencefalografia , Humanos , Recém-Nascido
18.
Clin Neurophysiol ; 111(9): 1646-53, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10964078

RESUMO

OBJECTIVE: This study aimed at identifying the characteristics - especially the duration - of rhythmic discharges in neonatal EEG, and their association with clinical neonatal problems. Specifically, we aimed at testing the diagnostic and prognostic validity of using 10 s as minimal duration for defining electroencephalographic seizures. DESIGN AND METHODS: The polysomnographies of 340 neonates were reviewed, and episodes of rhythmic discharges were identified, analyzed, and quantified. The study sample was divided into 3 groups: one in which the maximal duration of rhythmic discharges was shorter than 10 s (brief rhythmic discharges, BRD), a second one in which there were rhythmic discharges longer than 10 s (long rhythmic discharges, LRD), and finally a group in which no rhythmic discharge was found (No-RD). These 3 groups of subjects were compared for the baseline and outcome clinical data. RESULTS: From the 340 neonates studied, 210 did not present any form of rhythmic discharge, 67 (19. 7%) had only BRD episodes, and 63 (18.5%) had at least one LRD episode. Prevalence of rhythmic discharges was low among healthy full term newborns, and was significantly higher among preterm and high-risk newborns. Electrophysiological characteristics of rhythmic discharges did not differ between healthy neonates and high-risk ones. Accompanying clinical manifestations were present in 26.3% of the LRD group, but also in 15.9% of the BRD group. The presence of BRD was significantly associated with leukomalacia and with hypoglycemia in the cross-sectional analysis of baseline data, and with an increased risk for abnormal neurodevelopmental outcome after a mean follow-up period of 47 months (adjusted relative risk=4.90, P<0.01). CONCLUSIONS: The present data demonstrate an association between BRD and clinical history of hypoxic-ischemic encephalopathy, especially when complicated by leukomalacia, and also with a prognosis of increased risk for abnormal neurodevelopmental outcome. The clinical and prognostic significance of isolated BRD justifies the need to include these brief episodes in future studies of neonatal seizures.


Assuntos
Encéfalo/fisiopatologia , Eletroencefalografia , Epilepsia/diagnóstico , Epilepsia/fisiopatologia , Triagem Neonatal , Humanos , Recém-Nascido , Polissonografia , Prognóstico
19.
Clin Neurophysiol ; 111(2): 305-10, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10680566

RESUMO

OBJECTIVE: This study focuses on the characteristics of frontal sharp transients (FST), a normal variant of neonatal EEG, in newborns with hypoglycemia. METHODS: The EEG from 20 newborns with symptomatic hypoglycemia were compared with a control group of normal newborns matched by conceptional age. The dynamics of these transients were evaluated concerning sleep stages. The density, type and bilateral synchrony of FST were also calculated. The results were compared in the two groups by Student's t test. RESULTS: When compared with controls, hypoglycemic newborns have increased density of frontal sharp transients in all sleep stages but less bilateral synchrony (P<0.05). FST density was even higher in small for gestational age newborns. CONCLUSIONS: The data suggests that normal patterns of neonatal EEG as FST can be influenced by systemic disturbances.


Assuntos
Lobo Frontal/fisiopatologia , Hipoglicemia/fisiopatologia , Eletroencefalografia , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Masculino , Polissonografia , Fases do Sono/fisiologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA