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1.
Bratisl Lek Listy ; 120(10): 794-801, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31663357

RESUMO

BACKGROUND: Intraoperative neuromonitoring using tc-MEPs satisfactorily detects motor tract integrity changes during spinal surgery. However, tc-MEP is affected by anesthesia and other factors, in which the stimulation threshold increases because the waveform amplitude decreases over time with the accumulation and boluses of anesthetics. METHODS: We conducted a retrospective study of 139 patients. The average age was 30 years. Tc-MEPs were recorded bilaterally from the tibialis anterior muscle and the abductor hallucis muscle. Statistical tests were used to investigate the changes to evaluate anesthetic effects. RESULTS: There were no significant differences in tc-MEP amplitude change (%) between the groups of propofol (13 %), remifentanil (22 %) and sufentanil (26 %, p < 0.01). Significant differences were found between the groups of propofol, remifentanil, and sufentanil (20 %) and bolus sufentanil (‒30 %), and bolus ketamine (730 %, p < 0.008). Major differences were observed between bolus sufentanil (‒30 %) and bolus ketamine (730 %, p < 0.001). When comparing tc-MEPs with no amplitude, no significant difference was found between the groups of propofol (26 %), remifentanil (24 %), and sufentanil (28 %, p < 0.007). Substantial difference was found between the groups of propofol, remifentanil, and sufentanil (mean 26 %) and the group where ketamine boluses were administered. We didn't observe any loss of amplitude (0 %, p < 0.0002). CONCLUSION: IONM may be useless in patients where boluses of sufentanil are administered and also with Medical Research Council grades 3 and below. Consider applying IONM in patients with severe spinal deformity along with a higher age of over 50 and neurological deficit. Increasing stimulus intensity or facilitation techniques may be considered to improve the usefulness of tc-MEP. Our concept of findings supports the neurophysiological monitoring findings in other studies (Tab. 10, Ref. 45).


Assuntos
Anestesia , Monitorização Neurofisiológica Intraoperatória , Coluna Vertebral/cirurgia , Adulto , Anestésicos Intravenosos , Potencial Evocado Motor , Humanos , Ketamina/administração & dosagem , Propofol/administração & dosagem , Remifentanil/administração & dosagem , Estudos Retrospectivos , Sufentanil/administração & dosagem
2.
Neuroradiology ; 57(9): 903-8, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26022355

RESUMO

INTRODUCTION: Imaging has an essential role in the evaluation of correct positioning of electrodes implanted for deep brain stimulation (DBS). Although MRI offers superior anatomic visualization of target sites, there are safety concerns in patients with implanted material; imaging guidelines are inconsistent and vary. The fusion of postoperative CT with preoperative MRI images can be an alternative for the assessment of electrode positioning. The purpose of this study was to assess the accuracy of measurements realized on fused images (acquired without a stereotactic frame) using a manufacturer-provided software. METHODS: Data from 23 Parkinson's disease patients who underwent bilateral electrode placement for subthalamic nucleus (STN) DBS were acquired. Preoperative high-resolution T2-weighted sequences at 3 T, and postoperative CT series were fused using a commercially available software. Electrode tip position was measured on the obtained images in three directions (in relation to the midline, the AC-PC line and an AC-PC line orthogonal, respectively) and assessed in relation to measures realized on postoperative 3D T1 images acquired at 1.5 T. RESULTS: Mean differences between measures carried out on fused images and on postoperative MRI lay between 0.17 and 0.97 mm. CONCLUSION: Fusion of CT and MRI images provides a safe and fast technique for postoperative assessment of electrode position in DBS.


Assuntos
Mapeamento Encefálico/métodos , Estimulação Encefálica Profunda , Eletrodos Implantados , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Doença de Parkinson/cirurgia , Tomografia Computadorizada por Raios X/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Período Pré-Operatório , Núcleo Subtalâmico
3.
Orig Life Evol Biosph ; 43(2): 151-60, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23494128

RESUMO

The aim of this work is to study the features of a simple replicator chemical model of the relation between kinetic stability and entropy production under the action of external perturbations. We quantitatively explore the different paths leading to evolution in a toy model where two independent replicators compete for the same substrate. To do that, the same scenario described originally by Pross (J Phys Org Chem 17:312-316, 2004) is revised and new criteria to define the kinetic stability are proposed. Our results suggest that fast replicator populations are continually favored by the effects of strong stochastic environmental fluctuations capable to determine the global population, the former assumed to be the only acting evolution force. We demonstrate that the process is continually driven by strong perturbations only, and that population crashes may be useful proxies for these catastrophic environmental fluctuations. As expected, such behavior is particularly enhanced under very large scale perturbations, suggesting a likely dynamical footprint in the recovery patterns of new species after mass extinction events in the Earth's geological past. Furthermore, the hypothesis that natural selection always favors the faster processes may give theoretical support to different studies that claim the applicability of maximum principles like the Maximum Metabolic Flux (MMF) or Maximum Entropy Productions Principle (MEPP), seen as the main goal of biological evolution.


Assuntos
Evolução Biológica , Evolução Molecular , Modelos Químicos , Modelos Teóricos , Planeta Terra , Entropia , Meio Ambiente , Seleção Genética , Processos Estocásticos
4.
Euro Surveill ; 18(11): 20422, 2013 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-23517870

RESUMO

We describe the outbreak investigation associated with an unusual increase in Salmonella Goldcoast cases in Hungary observed in autumn 2009, which included descriptive and analytical epidemiological studies and microbiological and veterinary investigations. Sixty cases were identified between 1 January 2009 and 1 March 2010, 50 of them from late July 2009 to January 2010. Of 50 S. Goldcoast isolates, 44 showed an indistinguishable pulsed-field gel electrophoresis profile. We conducted a matched case-control study that indicated a statistically significant association between S. Goldcoast infection and the consumption of pork cheese. The majority of cases (seven of nine) reporting consumption of this product belonged to a single family cluster. After removing six cases of this cluster, pork cheese still showed an elevated but non-significant risk for being a case in the univariable analysis (Mantel-Haenszel odds ratio (MH OR): 3.87, 95% confidence interval (CI): 0.38-39.47). A single S. Goldcoast isolate was identified during routine veterinary surveillance activities in 2009 in minced beef from a butcher's shop, originating from an abattoir where also pigs were slaughtered. We conclude that the outbreak was probably due to multiple sources of contaminated meat, probably pork, released on the market over a period of several months in 2009.


Assuntos
Doenças Transmitidas por Alimentos/epidemiologia , Conhecimentos, Atitudes e Prática em Saúde , Intoxicação Alimentar por Salmonella/epidemiologia , Estudos de Casos e Controles , Queijo/microbiologia , Notificação de Doenças , Surtos de Doenças , Microbiologia de Alimentos/normas , Doenças Transmitidas por Alimentos/microbiologia , Humanos , Hungria/epidemiologia , Produtos da Carne/microbiologia , Vigilância da População , Salmonella/classificação , Salmonella/isolamento & purificação , Intoxicação Alimentar por Salmonella/microbiologia , Fatores Socioeconômicos , Inquéritos e Questionários , Vômito/complicações
5.
Euro Surveill ; 18(5)2013 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-23399425

RESUMO

Within the Influenza Monitoring Vaccine Effectiveness in Europe (I-MOVE) project we conducted a multicentre case­control study in eight European Union (EU) Member States to estimate the 2011/12 influenza vaccine effectiveness against medically attended influenza-like illness (ILI) laboratory-confirmed as influenza A(H3) among the vaccination target groups. Practitioners systematically selected ILI / acute respiratory infection patients to swab within seven days of symptom onset. We restricted the study population to those meeting the EU ILI case definition and compared influenza A(H3) positive to influenza laboratory-negative patients. We used logistic regression with study site as fixed effect and calculated adjusted influenza vaccine effectiveness (IVE), controlling for potential confounders (age group, sex, month of symptom onset, chronic diseases and related hospitalisations, number of practitioner visits in the previous year). Adjusted IVE was 25% (95% confidence intervals (CI): -6 to 47) among all ages (n=1,014), 63% (95% CI: 26 to 82) in adults aged between 15 and 59 years and 15% (95% CI: -33 to 46) among those aged 60 years and above. Adjusted IVE was 38% (95%CI: -8 to 65) in the early influenza season (up to week 6 of 2012) and -1% (95% CI: -60 to 37) in the late phase. The results suggested a low adjusted IVE in 2011/12. The lower IVE in the late season could be due to virus changes through the season or waning immunity. Virological surveillance should be enhanced to quantify change over time and understand its relation with duration of immunological protection. Seasonal influenza vaccines should be improved to achieve acceptable levels of protection.


Assuntos
Vírus da Influenza A Subtipo H3N2/imunologia , Vírus da Influenza A Subtipo H3N8/imunologia , Vacinas contra Influenza/administração & dosagem , Influenza Humana/epidemiologia , Influenza Humana/prevenção & controle , Vacinação/estatística & dados numéricos , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Criança , Pré-Escolar , Intervalos de Confiança , Europa (Continente)/epidemiologia , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Lactente , Recém-Nascido , Vírus da Influenza A Subtipo H3N2/isolamento & purificação , Vírus da Influenza A Subtipo H3N8/isolamento & purificação , Vacinas contra Influenza/imunologia , Influenza Humana/imunologia , Influenza Humana/virologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Nasofaringe/virologia , Nariz/virologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Estações do Ano , Vigilância de Evento Sentinela , Resultado do Tratamento , Adulto Jovem
7.
Eur Arch Paediatr Dent ; 22(1): 57-65, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32323224

RESUMO

AIMS: To validate the Child-Oral Impact on Daily Performance (Child-OIDP) in the Hungarian language and to explore the oral health-related quality of life (OHRQoL) and associated factors among Hungarian children with cleft lip or/and palate (CLP). METHODS: This cross-sectional study consists of a survey and clinical examination among conveniently selected children with CLP visiting the Pécs cleft lip and palate clinic, Pécs, Hungary. OHRQoL was assessed using the Hungarian version of Child-OIDP. Additionally, a validated structural questionnaire was used for gathering information related to oral hygiene practice. Clinical examination was done to register the dental status using ICDAS criteria, consequences of untreated dental caries (pufa), and bleeding on probing. Results were presented as proportions, means, and standard deviations (SD). Construct validity and internal reliability of the Hungarian Child-OIDP was assessed using the Pearson and Spearman's correlation coefficients, respectively. The logistic regression model examined the association between OHRQoL and explanatory variables. RESULTS: A total of 45 children with CLP participated in this study. The Hungarian Child-OIDP had the Cronbach's alpha value 0.73, and the Spearman's correlation coefficient was 0.31. The mean (SD) Child-OIDP score among the study participants was 4.4 (7.0) and three-fifths (65.9%, n = 27) of the participants reported impact in one or more items of the OHRQoL scale. Tooth brushing was more frequent among 6-10-year-olds compared to 11-16-year-olds. The proportion of those requiring restorative treatment need (DS ≥ 1) was 90.2% (n = 37), those with PUFA/pufa (score ≥ 1) was 24.4% (n = 10), and those with bleeding on probing (> 15%) was 63.4% (n = 26). Children aged 11-16 years had a higher impact on OHRQoL compared to the younger ones. Girls had a higher impact on OHRQoL compared to boys. Children with clefts involving both lip and palate had poorer OHRQoL than the rest. The same was true for those having a high dental caries rate. CONCLUSION: The Hungarian Child-OIDP was a reliable and valid measure. There was a substantial impact on OHRQoL among Hungarian children and adolescents with CLP. Age, gender, cleft type and dental caries were associated with poor OHRQoL.


Assuntos
Fenda Labial , Fissura Palatina , Cárie Dentária , Adolescente , Criança , Estudos Transversais , Cárie Dentária/epidemiologia , Feminino , Humanos , Hungria/epidemiologia , Idioma , Masculino , Saúde Bucal , Qualidade de Vida , Reprodutibilidade dos Testes , Inquéritos e Questionários
8.
Regul Toxicol Pharmacol ; 57(1): 55-61, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20043970

RESUMO

The dietary supplement, 112 Degrees, was formulated with the goal of supporting sexual functioning in men. Due to rampant problems with drug adulteration for this category of products, a comprehensive screening for active pharmaceutical agents, with an emphasis on drugs prescribed for erectile dysfunction such as type 5 phosphodiesterase (PDE-5) inhibitors, and known unapproved PDE-5 drug analogues, was performed along with preclinical toxicology studies prior to the introduction of this product into the marketplace. 112 Degrees was found to be free of all pharmaceutical adulterants tested, and was not mutagenic, clastogenic, or genotoxic as demonstrated by the Ames test, chromosomal aberration assay, and mouse micronucleus assay, respectively. The LD(50) in the 14-day acute oral toxicity study was greater than 5000 mg/kg, the highest dose tested.


Assuntos
Qualidade de Produtos para o Consumidor , Suplementos Nutricionais/toxicidade , Comportamento Sexual/efeitos dos fármacos , Animais , Células CHO , Cricetinae , Cricetulus , Relação Dose-Resposta a Droga , Contaminação de Medicamentos , Avaliação Pré-Clínica de Medicamentos , Feminino , Humanos , Dose Letal Mediana , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Micronúcleos com Defeito Cromossômico/induzido quimicamente , Testes para Micronúcleos , Mutação , Ratos , Ratos Sprague-Dawley , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/genética , Testes de Toxicidade Crônica
9.
Acta Chir Orthop Traumatol Cech ; 77(2): 112-7, 2010 Apr.
Artigo em Sk | MEDLINE | ID: mdl-20447353

RESUMO

PURPOSE OF THE STUDY: To evaluate the effect of complications on the quality of life in patients after elective stabilisation surgery on the lumbar spine. MATERIAL AND METHODS: Between January 2005 and June 2007, 208 patients (120 women and 88 men) were included in the prospective study carried out at our department. These patients were undergoing elective surgery for lumbar spinal disease, namely, central and lateral stenosis, degenerative disc disease and degenerative and isthmic spondylolisthesis. All patients were treated by transpedicular fixation and fusion involving transforaminal lumbar interbody fusion (TLIF) in 165 patients, anterior lumbar interbody fusion (ALIF) in five and posterolateral fusion (PLF) in 38 patients. Satisfaction of the patients with surgery outcomes was assessed on a three-point scale, using the Visual Analogue Scale (VAS), and the Short Form health survey questionnaire (SF-36v2) for life quality evaluation. The follow-up period ranged from 6 months to 2 years. The results were statistically analysed using the chi-square test and t-test. RESULTS: A total of 30 complications were recorded in 28 patients (13.5 %). Revision surgery was necessary in 18 patients (8.7%). Pedicle screw misplacement was found in eight patients and permanent neurological deficit with paresis of the unilateral lower limb in three patients. Carbon cage break-down during surgery occurred in one patient, misinsertion of the cage was in one patient. The dural sac was damaged in five patients, superficial and deep wound infection was found in four and two patients, respectively. Broken screws were detected in seven patients. Donor-site pain persisted in two patients. The patients free from complications were more satisfied (partial or full satisfaction in 86%) than the patients with complications, who reported satisfaction in 78%. However, the difference was not statistically significant. The complications had no significant effect on either any of the SF-36v2 health domains or the total physical and mental score or pain intensity. The ALIF procedure was associated with no complications, PLF with three (13%) and TLIF with 23 (14%) complications, but the differences were not statistically significant. DISCUSSION: Complications and revision surgery were relatively frequent in our group, but not excessive compared with the published data which report their occurrence from 3% to 30%. This large range is related to an ambiguous definition and specification of complications. A significantly fewer complications have been reported in the studies supported by companies, or in those in which the author/s participate in instrumentation development. Some studies suggest that novel and more complex techniques bring about a higher risk of complications and repeat surgery, others report better results and fewer reoperations following a 360-degree fusion than after PLF. The difference in complications between TLIP and PLF in our group was not significant. CONCLUSIONS: Complications are a serious issue of spinal surgery. The majority of complications in our group were associated instrumentation--most frequently with incorrect screw misinsertion. On the whole, the complications did not significantly influence the quality of life and pain intensity after surgery. Most of them were treated successfully with no permanent consequences. The permanent neurological deficit in three patients, because of the small number, had no effect on the whole group results. A reduction in the number of complications would not produce any expected improvement of functional out- come.


Assuntos
Vértebras Lombares/cirurgia , Qualidade de Vida , Doenças da Coluna Vertebral/cirurgia , Fusão Vertebral/efeitos adversos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Reoperação
10.
Bratisl Lek Listy ; 111(5): 290-5, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20568421

RESUMO

OBJECTIVES: Our goal was to evaluate the quality of life in patients who underwent an elective lumbar stabilization and fusion. MATERIALS AND METHODS: We treated 208 patients (120 females and 88 males) for degenerative lumbar spine conditions. In 165 cases we performed the transforaminal lumbar interbody fusion (TLIF), in 38 the posterolateral lumbar fusion (PLF) and in 5 the anterior lumbar interbody fusion (ALIF). Before and after the surgery, pain was evaluated with the VAS and the quality of life with the second version of the SF-6. Follow up was from six months to two years. We used the statistical tests chi-square, t-test and ANOVA. RESULTS: Satisfied were 62.5% of patients, partially satisfied were 19.7% and dissatisfied were 17.8% of patients. The average VAS decreased from 68 to 35. There was a significant improvement in mobility and decrease of consumption of analgetics after the surgery. Clinically significant improvements were in all domains of sf-36 except the mental health, social function and mental composite score. We had 30 complications in 28 patients. A revision surgery was necessary in 18 cases. Complications had no significant effect on the SF-36 and VAS score. CONCLUSION: The results are comparable with published data. Correctly indicated spinal operations are effective in reducing pain and improvement of the function. We have noted a significant decrease of pain, improvement of mobility, and a reduction of analgetics consumption. Despite the improvements, post-operatively all values of the SF-36 were lower than standards for the population. Complications and reoperations in our group are relatively common problems, surprisingly did not affected the quality of life after surgery (Tab. 9, Ref. 38). Full Text (Free, PDF) www.bmj.sk.


Assuntos
Vértebras Lombares/cirurgia , Qualidade de Vida , Fusão Vertebral , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Satisfação do Paciente , Fusão Vertebral/efeitos adversos , Fusão Vertebral/psicologia
12.
Orig Life Evol Biosph ; 39(6): 533-44, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19554472

RESUMO

Oscillating biochemical reactions are common in cell dynamics and could be closely related to the emergence of the life phenomenon itself. In this work, we study the dynamical features of some classical chemical or biochemical oscillators where the effect of cell volume changes is explicitly considered. Such analysis enables us to find some general conditions about the cell membrane to preserve such oscillatory patterns, of possible relevance to hypothetical primitive cells in which these structures first appeared.


Assuntos
Relógios Biológicos , Termodinâmica , Membrana Celular/metabolismo , Tamanho Celular , Modelos Biológicos
13.
Artigo em Inglês | MEDLINE | ID: mdl-30224931

RESUMO

Arthritic diseases are the most frequent causes of chronic pain and disability. Rheumatoid arthritis (RA) is an autoimmune disease characterized by synovial inflammation and progressive structural joint damage. Osteoarthritis is a degenerative process of the articular cartilage associated with hypertrophic changes in the bone. The aim of the present study was to investigate the anti-inflammatory and analgesic effects of Hévíz thermal water and mud in monosodium iodoacetate- (MIA-) (25 mg/ml, 20 µl i.a.) induced osteoarthritis and Complete Freund's adjuvant- (CFA-) (1 mg/ml, 50-50 µl s.c) induced rheumatoid arthritis murine models. The mechanonociceptive threshold of female NMRI mice (n=6- 8 mice/ group) was measured by aesthesiometry, and paw volume was monitored with plethysmometry, knee joint diameter with digital micrometer, and dynamic weight bearing on the hind limbs with a Bioseb instrument. Periarticular bone destruction was assessed by SkyScan 1176 in vivo micro-CT. Inflammatory cytokines were detected by ELISA in plasma samples. Treatments (30 min, every working day) with tap water, sand, and a combined therapy of tap water and sand served as controls. Hévíz medicinal water and combined treatment with water and mud significantly decreased the mechanical hyperalgesia and knee oedema in MIA-induced osteoarthritis model. However, balneotherapy did not influence mechanical hyperalgesia, weight bearing, or oedema formation induced by CFA. Neither medicinal water nor mud treatment ameliorated deep structural damage of the bones or the joints in the animal models. On the basis of the present findings, we conclude that balneotherapy is an effective complementary treatment to reduce the pain sensation and swelling in degenerative joint diseases such as osteoarthritis. Our experimental data are in agreement with the previous human studies that also confirmed antinociceptive and anti-inflammatory effects of thermal water and Hévíz mud treatments.

14.
J Geod ; 93: 2249-2262, 2018 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31920222

RESUMO

For over 40 years, NASA's global network of satellite laser ranging (SLR) stations has provided a significant percentage of the global orbital data used to define the International Terrestrial Reference Frame (ITRF). The current NASA legacy network is reaching its end-of-life and a new generation of systems must be ready to take its place. Scientific demands of sub-millimeter precision ranging and the ever-increasing number of tracking targets give aggressive performance requirements to this new generation of systems. Using lessons learned from the legacy systems and the successful development of a prototype station, a new network of SLR stations, called the Space Geodesy Satellite Laser Ranging (SGSLR) systems, is being developed. These will be the state-of-the-art SLR component of NASA's Space Geodesy Project (SGP). Each of SGSLR's nine subsystems has been designed to produce a robust, kilohertz laser ranging system with 24/7 operational capability and with minimal human intervention. SGSLR's data must support the aggressive goals of the Global Geodetic Observing System (GGOS), which are 1 millimeter (mm) position accuracy and 0.1 mm per year stability of the ITRF. This paper will describe the major requirements and accompanying design of the new SGSLR systems, how the systems will be tested, and the expected system performance.

15.
J Clin Invest ; 52(12): 3028-32, 1973 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-4750439

RESUMO

In studies on seven anephric patients, glucose and insulin administration before hemodialysis produced a significant reduction in plasma potassium concentration (mean reduction = 1.3, 1.7, and 1.4 meq/liter at 60, 120, and 180 min, respectively) which was accompanied by a significant and sustained reduction in plasma aldosterone concentration. There was a significant correlation between plasma aldosterone and plasma potassium concentration (r = +0.74, P < 0.001) and between changes in the concentration of plasma aldosterone occurring in individual patients and the corresponding changes in plasma potassium concentration (r = +0.52, P < 0.01). There was no significant change in plasma sodium concentration, and plasma corticoid concentration, which was monitored as an index of ACTH elaboration, was reduced at 60 min but increased subsequently as symptoms attributable to hypoglycemia were observed. These studies demonstrate that plasma aldosterone concentration can be modulated acutely by transitory changes in plasma potassium concentration without a change in potassium balance. The effect of glucose and insulin administration on intracellular potassium in the adrenal cortex is uncertain, and although increased net movement of potassium into cells is the presumptive mechanism of the reduction in plasma potassium concentration, whether the potassium content of the adrenal cortex may have increased or decreased or remained essentially unchanged, cannot be inferred from our data.


Assuntos
Aldosterona/sangue , Rim/fisiologia , Potássio/sangue , Aldosterona/metabolismo , Glucocorticoides/sangue , Glucose/farmacologia , Humanos , Insulina/farmacologia , Radioimunoensaio , Diálise Renal
16.
Neuroscience ; 147(1): 28-36, 2007 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-17499931

RESUMO

Alzheimer's disease is characterized by the presence of senile plaques in the brain, composed mainly of aggregated amyloid-beta peptide (Abeta), which plays a central role in the pathogenesis of Alzheimer's disease and is a potential target for therapeutic intervention. Amyloid plaques occur in an increasing number of brain structures during the progression of the disease, with a heavy load in regions of the temporal cortex in the early phases. Here, we investigated the cognitive deficits specifically associated with amyloid pathology in the entorhinal cortex. The amyloid peptide Abeta(1-42) was injected bilaterally into the entorhinal cortex of rats and behavioral performance was assessed between 10 and 17 days after injection. We found that parameters of motor behavior in an open-field as well as spatial working memory tested in an alternation task were normal. In contrast, compared with naive rats or control rats injected with saline, rats injected with Abeta(1-42) showed impaired recognition memory in an object recognition task and delayed acquisition in a spatial reference memory task in a water-maze, despite improved performance with training in this task and normal spatial memory in a probe test given 24 h after training. This profile of behavioral deficits after injection of Abeta(1-42) into the entorhinal cortex was similar to that observed in another group of rats injected with the excitotoxic drug, N-methyl-d-aspartate. Immunohistochemical analysis after behavioral testing revealed that Abeta(1-42) injection induced a reactive astroglial response and plaque-like deposits in the entorhinal cortex. These results show that experimentally-induced amyloid pathology in the entorhinal cortex induces selective cognitive deficits, resembling those observed in early phases of Alzheimer's disease. Therefore, injection of protofibrillar-fibrillar Abeta(1-42) into the entorhinal cortex constitutes a promising animal model for investigating selective aspects of Alzheimer's disease and for screening drug candidates designed against Abeta pathology.


Assuntos
Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Modelos Animais de Doenças , Córtex Entorrinal/patologia , Fragmentos de Peptídeos/metabolismo , Placa Amiloide/metabolismo , Reconhecimento Psicológico/fisiologia , Doença de Alzheimer/complicações , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/administração & dosagem , Animais , Transtornos Cognitivos/induzido quimicamente , Transtornos Cognitivos/complicações , Transtornos Cognitivos/metabolismo , Transtornos Cognitivos/patologia , Córtex Entorrinal/metabolismo , Córtex Entorrinal/fisiopatologia , Comportamento Exploratório/fisiologia , Gliose/induzido quimicamente , Gliose/metabolismo , Masculino , Aprendizagem em Labirinto/fisiologia , Microinjeções , N-Metilaspartato , Neurotoxinas , Fragmentos de Peptídeos/administração & dosagem , Placa Amiloide/patologia , Ratos , Ratos Wistar , Estatísticas não Paramétricas
18.
Hear Res ; 225(1-2): 117-27, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17300890

RESUMO

The analysis of the auditory scene begins from the moment we hear sounds, making it possible for the infant to distinguish the mother's voice from other sounds in the environment. The purpose of the study was to determine, in two experiments, whether the frequency separation threshold, at which the perception of a mixture of sounds turns from being perceived as one stream to two streams, differs between two groups of school-aged children (ages 5-8 and 9-11 years) and adults. The results show a developmental course for the perception of auditory streams that is not simply dependent upon frequency discrimination. This suggests that maturation of the stream segregation process follows a longer developmental course than maturation of simple feature discrimination. The data indicate that the ability to hear distinct sound streams in the environment takes time to develop and becomes sharpened with experience and maturity.


Assuntos
Percepção Auditiva/fisiologia , Estimulação Acústica , Adulto , Fatores Etários , Criança , Desenvolvimento Infantil/fisiologia , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Discriminação da Altura Tonal/fisiologia , Percepção da Altura Sonora/fisiologia
19.
Plant Dis ; 91(3): 331, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30780595

RESUMO

Economically important viruses such as Tomato spotted wilt virus, genus Tospovirus, are transmissible mechanically and mainly by two thrips species (Thrips tabaci and Frankliniella occidentalis) in Hungary (1). Samples (31) of eight ornamental plant species (Catharanthus roseus, Cyclamen persicum, Dendranthema × grandiflorum, Eustoma grandiflorum, Gerbera sp., Impatiens walleriana, Ocimum basilicum, and Verbena hybrida) were studied. Symptoms including color breaking on flowers and necrotic symptoms on leaves were observed on four samples (C. persicum, I. walleriana, O. basilicum, and E. grandiflorum). Infection by Impatiens necrotic spot virus (INSV) was determined by double-antibody sandwich-ELISA and triple-antibody sandwich-ELISA using antisera obtained from Loewe (Sauerlach, Germany) and the DSMZ. Back inoculation with the F. occidentalis vector was also carried out to Lycopersicon esculentum as indicator plants. Back inoculation was also positive for INSV by symptoms and ELISA. The high amount of ornamental plant production together with the use of virus-infected propagation material and the increasing thrips vector populations may result in significantly increased establishment and distribution of INSV in Hungary. References: (1) M. L. Daughtrey et al. Plant Dis. 81:1220, 1997.

20.
Chem Commun (Camb) ; 53(36): 4973-4976, 2017 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-28425528

RESUMO

Periodic length changes, over 20%, were sustained in a pH-responsive gel by associating the methylene glycol-sulphite OH-producing clock-reaction with variations of the exchange time induced between the core of the gel and a steady chemical environment. This is the first synergistic actuator that operates beyond acid-producing redox reactions.

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