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1.
Urologiia ; (2 Suppl 2): 103-110, 2016 Apr.
Artigo em Russo | MEDLINE | ID: mdl-28247652

RESUMO

Numerous metabolic abnormalities intrinsic to urolithiasis require drug therapy. At the same time, despite the constant expansion of synthetic drugs, plant-derived medications play a large role in the treatment and prevention of the disease. AIM: To evaluate the effect of a plant-derived preparation Rowatinex in patients with urolithiasis after extracorporeal shock wave lithotripsy (ESWL) and analyze the changes in blood and urine parameters in patients receiving the preparation. MATERIALS AND METHODS: Depending on the type of post-ESWL treatment, patients were divided into two groups. After ESWL, patients of group A (n=107) and group B (n=50) were administered Rowatinex and antispasmodic drugs, respectively. RESULTS AND DISCUSSION: Clearance of stone fragments after ESWL within 1-5 days was achieved in 76 (71.1%) patients of group A and in 20 (40.4%) of group B. Analysis of the effect of the therapy on blood count, biochemistry tests and 24h excretion (magnesium, uric acid, calcium, etc.) did not reveal significant differences between group A group B and reference values. Increased diuresis caused by antispasmodic effects of Rowatinex resulted in the complete clearance of stone fragments. Urinalysis in patients of the two groups showed decreased leukocyturia. Furthermore, stabilization of urine pH within the 6.2-6.8 was noted in group A, which is important and necessary in metaphylaxis of recurrent stone formation. CONCLUSIONS: Administration of Rowatinex increases the percentage of stone fragment clearance after ESWL and reduces pain intensity. Rowatinex reduces leukocyturia, increases 24h diuresis and stabilizes the pH of urine. Increasing and stabilizing urine pH in patients with calcium oxalate and urate stones reduces the risk of recurrence after ESWL. No complications associated with Rowatinex were reported, allowing long-term administration of the preparation in the complex lithokinetic therapy and for metaphylaxis of recurrent stone formation.


Assuntos
Litotripsia , Preparações de Plantas/administração & dosagem , Terpenos/administração & dosagem , Urolitíase/terapia , Feminino , Humanos , Masculino , Urolitíase/urina
2.
Urologiia ; (5): 16-20, 2016 Nov.
Artigo em Russo | MEDLINE | ID: mdl-28248014

RESUMO

INTRODUCTION: Currently, extracorporeal shock wave lithotripsy (ESWL) is a minimally invasive treatment for patients with urolithiasis. With advancing medical technology, elastography has evolved as a method for measuring the elasticity of tissues. AIM: To investigate the elasticity of urinary stones for assessing their physical and chemical composition. MATERIALS AND METHODS: The elasticity of urinary stones was determined before ESWL in 30 urolithiasis patients (18 men and 12 women, aged 25-65 years) using shear wave ultrasound elastography (SWUE). In 40%, 23.3% and 20% of patients, urinary stones were located in the renal pelvis, the middle calyceal group and the lower calyceal group, respectively. RESULTS: Elastography is a method of determining the elasticity of urinary stones, measured in kPa. Mean elasticity (Emean) of calcium oxalate monohydrate stones, uric acid stones and mixed urinary stones was 39.8, 14.6 and 26.3-29.8 kPa, respectively. Urinary stones smaller than 5 mm did not differ in the color spectrum. Excess body mass index (BMI) also reduced the informative value of the method. CONCLUSIONS: The findings of SWUE are comparable with the results of computer densitometry and physical and chemical composition of the investigated urinary stones.


Assuntos
Cálculos Urinários/química , Adulto , Idoso , Técnicas de Imagem por Elasticidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
3.
Nat Neurosci ; 18(9): 1291-1298, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26237367

RESUMO

Hippocampal pathology is likely to contribute to cognitive disability in Down syndrome, yet the neural network basis of this pathology and its contributions to different facets of cognitive impairment remain unclear. Here we report dysfunctional connectivity between dentate gyrus and CA3 networks in the transchromosomic Tc1 mouse model of Down syndrome, demonstrating that ultrastructural abnormalities and impaired short-term plasticity at dentate gyrus-CA3 excitatory synapses culminate in impaired coding of new spatial information in CA3 and CA1 and disrupted behavior in vivo. These results highlight the vulnerability of dentate gyrus-CA3 networks to aberrant human chromosome 21 gene expression and delineate hippocampal circuit abnormalities likely to contribute to distinct cognitive phenotypes in Down syndrome.


Assuntos
Região CA3 Hipocampal/fisiopatologia , Cromossomos Humanos Par 21 , Giro Denteado/fisiopatologia , Modelos Animais de Doenças , Síndrome de Down/fisiopatologia , Rede Nervosa/fisiopatologia , Animais , Região CA3 Hipocampal/patologia , Cromossomos Humanos Par 21/genética , Giro Denteado/patologia , Síndrome de Down/genética , Síndrome de Down/patologia , Humanos , Masculino , Aprendizagem em Labirinto/fisiologia , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Rede Nervosa/patologia , Técnicas de Cultura de Órgãos , Trissomia/genética
4.
Neuroscience ; 303: 364-77, 2015 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-26166731

RESUMO

A central component of Attention-Deficit Hyperactivity Disorder (ADHD) is increased distractibility, which is linked to the superior colliculus (SC) in a range of species, including humans. Furthermore, there is now mounting evidence of altered collicular functioning in ADHD and it is proposed that a hyper-responsive SC could mediate the main symptoms of ADHD, including distractibility. In the present study we have provided a systematic characterization of the SC in the most commonly used and well-validated animal model of ADHD, the spontaneously hypertensive rat (SHR). We examined collicular-dependent orienting behavior, local field potential (LFP) and multiunit responses to visual stimuli in the anesthetized rat and morphological measures in the SHR in comparison to the Wistar Kyoto (WKY) and Wistar (WIS). We found that SHRs remain responsive to a repeated visual stimulus for more presentations than control strains and have a longer response duration. In addition, LFP and multiunit activity within the visually responsive superficial layers of the SC showed the SHR to have a hyper-responsive SC relative to control strains, which could not be explained by altered functioning of the retinocollicular pathway. Finally, examination of collicular volume, neuron and glia densities and glia:neuron ratio revealed that the SHR had a reduced ratio relative to the WKY which could explain the increased responsiveness. In conclusion, this study demonstrates strain-specific changes in the functioning and structure of the SC in the SHR, providing convergent evidence that the SC might be dysfunctional in ADHD.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/complicações , Transtorno do Deficit de Atenção com Hiperatividade/patologia , Transtornos da Percepção/etiologia , Colículos Superiores/fisiopatologia , Análise de Variância , Animais , Modelos Animais de Doenças , Eletroencefalografia , Potenciais Evocados Visuais/fisiologia , Masculino , Atividade Motora/fisiologia , Orientação/fisiologia , Estimulação Luminosa , Psicofísica , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Especificidade da Espécie , Colículos Superiores/patologia , Vias Visuais/patologia , Vias Visuais/fisiopatologia
5.
Brain Struct Funct ; 219(1): 407-14, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23224218

RESUMO

The formation of multiple spine boutons (MSBs) has been associated with cognitive abilities including hippocampal-dependent associative learning and memory. Data obtained from cultured hippocampal slices suggest that the long-term maintenance of synaptic plasticity requires the formation of new synaptic contacts on pre-existing synapses. This postulate however, has never been tested in the awake, freely moving animals. In the current study, we induced long-term potentiation (LTP) in the dentate gyrus (DG) of awake adult rats and performed 3-D reconstructions of electron micrographs from thin sections of both axonal boutons and dendritic spines, 24 h post-induction. The specificity of the observed changes was demonstrated by comparison with animals in which long-term depression (LTD) had been induced, or with animals in which LTP was blocked by an N-methyl-D-aspartate (NMDA) antagonist. Our data demonstrate that whilst the number of boutons remains unchanged, there is a marked increase in the number of synapses per bouton 24 h after the induction of LTP. Further, we demonstrate that this increase is specific to mushroom spines and not attributable to their division. The present investigation thus fills the gap existing between behavioural and in vitro studies on the role of MSB formation in synaptic plasticity and cognitive abilities.


Assuntos
Espinhas Dendríticas/fisiologia , Hipocampo/citologia , Hipocampo/fisiologia , Potenciação de Longa Duração/fisiologia , Sinapses/fisiologia , Vigília , Animais , Biofísica , Simulação por Computador , Espinhas Dendríticas/ultraestrutura , Estimulação Elétrica , Eletrodos Implantados , Antagonistas de Aminoácidos Excitatórios/farmacologia , Potenciação de Longa Duração/efeitos dos fármacos , Depressão Sináptica de Longo Prazo/efeitos dos fármacos , Depressão Sináptica de Longo Prazo/fisiologia , Masculino , Rede Nervosa/fisiologia , Rede Nervosa/ultraestrutura , Piperazinas/farmacologia , Ratos , Ratos Sprague-Dawley , Sinapses/ultraestrutura , Fatores de Tempo
6.
Sud Med Ekspert ; 57(6): 16-7, 2014.
Artigo em Russo | MEDLINE | ID: mdl-25764893

RESUMO

The present paper reports the results of the application of measurements of cadaveric tissue pressure (CTP) in forensic medical thanatology for the determination of the initial position of the corpse and the identification of the visually undetectable bleeding sites on the scalp during examination at the place of its discovery. Moreover, the study of the tissue pressure parameters in the affected tissues may be used to determine the intravitality of the injury and dynamics of its prescription. The parameters of intra-organ tissue pressure suggest its dependence not only on the prescription of the death and manifestations of the postmortem processes but also on the character and extent of the pathological process in the tissues of the organ of interest; these findings can be used for the verification of various diagnostic procedures including those for the objective elucidation of the cause of the death. It is concluded that the investigations along these lines extend the possibilities for the use of quantitative parameters of CTP for the substantiation of expert conclusions based on the results of forensic medical examination.


Assuntos
Cadáver , Patologia Legal/instrumentação , Patologia Legal/métodos , Pressão , Pele/patologia , Autopsia , Hemorragia/patologia , Humanos , Pele/irrigação sanguínea , Tanatologia
7.
Neuroscience ; 171(2): 390-7, 2010 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-20849931

RESUMO

Alterations in curvature of the post synaptic density (PSD) and apposition zone (AZ), are believed to play an important role in determining synaptic efficacy. In the present study we have examined curvature of PSDs and AZs 24 h following homosynaptic long-term potentiation (LTP), and heterosynaptic long-term depression (LTD) in vivo, in awake adult rats. High frequency stimulation (HFS) applied to the medial perforant path to the dentate gyrus induced LTP while HFS stimulation of the lateral perforant path induced LTD in the middle molecular layer of the dentate gyrus (DG). Curvature changes were analysed in this area using three dimensional (3-D) reconstructions of electron microscope images of ultrathin serial sections. Very large and significant changes in 3-D measurements of AZ and PSD curvature occurred 24 h following both LTP and LTD, with a flattening of the normal concavity of mushroom spine heads and a change to convexity for thin spines. An N-methyl-D-aspartate (NMDA) receptor antagonist CPP (3-[(R)-2-Carboxypiperazin-4-yl]-propyl-1-phosphonic acid) blocked the changes in curvature of mushroom and thin spine PSDs and apposition zones, actually increasing the concavity of mushroom spines as the spine engulfed the presynaptic bouton. In order to establish whether these changes resulted from the effect of the NMDA antagonist or from its coincidence with synaptic activation during testing we examined the effects of CPP alone on PSD and apposition zone curvature. It was found that CPP alone also caused a small decrease in curvature of both PSD and apposition zone of mushroom and thin spines.


Assuntos
Giro Denteado/efeitos dos fármacos , Potenciação de Longa Duração , Depressão Sináptica de Longo Prazo , Piperazinas/farmacologia , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Sinapses/efeitos dos fármacos , Animais , Espinhas Dendríticas/efeitos dos fármacos , Espinhas Dendríticas/ultraestrutura , Giro Denteado/fisiologia , Giro Denteado/ultraestrutura , Masculino , Densidade Pós-Sináptica/efeitos dos fármacos , Terminações Pré-Sinápticas/efeitos dos fármacos , Terminações Pré-Sinápticas/fisiologia , Ratos , Ratos Sprague-Dawley , Sinapses/fisiologia , Sinapses/ultraestrutura
8.
Neuroscience ; 165(4): 1170-81, 2010 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-19961908

RESUMO

Long-term morphological synaptic changes associated with homosynaptic long-term potentiation (LTP) and heterosynaptic long-term depression (LTD) in vivo, in awake adult rats were analyzed using three-dimensional (3-D) reconstructions of electron microscope images of ultrathin serial sections from the molecular layer of the dentate gyrus. For the first time in morphological studies, the specificity of the effects of LTP and LTD on both spine and synapse ultrastructure was determined using an N-methyl-d-aspartate (NMDA) receptor antagonist CPP (3-[(R)-2-carboxypiperazin-4-yl]-propyl-1-phosphonic acid). There were no differences in synaptic density 24 h after LTP or LTD induction, and CPP alone had no effect on synaptic density. LTP increased significantly the proportion of mushroom spines, whereas LTD increased the proportion of thin spines, and both LTP and LTD decreased stubby spine number. Both LTP and LTD increased significantly spine head evaginations (spinules) into synaptic boutons and CPP blocked these changes. Synaptic boutons were smaller after LTD, indicating a pre-synaptic effect. Interestingly, CPP alone decreased bouton and mushroom spine volumes, as well as post-synaptic density (PSD) volume of mushroom spines.These data show similarities, but also some clear differences, between the effects of LTP and LTD on spine and synaptic morphology. Although CPP blocks both LTP and LTD, and impairs most morphological changes in spines and synapses, CPP alone was shown to exert effects on aspects of spine and synaptic structure.


Assuntos
Espinhas Dendríticas/efeitos dos fármacos , Giro Denteado/efeitos dos fármacos , Antagonistas de Aminoácidos Excitatórios/farmacologia , Plasticidade Neuronal/efeitos dos fármacos , Piperazinas/farmacologia , Sinapses/efeitos dos fármacos , Animais , Espinhas Dendríticas/fisiologia , Espinhas Dendríticas/ultraestrutura , Giro Denteado/fisiologia , Giro Denteado/ultraestrutura , Potenciação de Longa Duração/efeitos dos fármacos , Potenciação de Longa Duração/fisiologia , Depressão Sináptica de Longo Prazo/efeitos dos fármacos , Depressão Sináptica de Longo Prazo/fisiologia , Masculino , Plasticidade Neuronal/fisiologia , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Neurônios/ultraestrutura , Terminações Pré-Sinápticas/efeitos dos fármacos , Terminações Pré-Sinápticas/fisiologia , Terminações Pré-Sinápticas/ultraestrutura , Ratos , Ratos Sprague-Dawley , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Receptores de N-Metil-D-Aspartato/metabolismo , Sinapses/fisiologia , Sinapses/ultraestrutura , Vigília
9.
Neuroscience ; 162(2): 254-67, 2009 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-19447163

RESUMO

A partial kindling procedure was used to investigate the correlation between focal seizure development and changes in dendritic spine morphology, ongoing neurogenesis and reactive astrogliosis in the adult rat dentate gyrus (DG). The processes of neurogenesis and astrogliosis were investigated using markers for doublecortin (DCX), 5-bromo-2-deoxyuridine (BrdU) and glial fibrillary acidic protein (GFAP). Our data demonstrate that mild focal seizures induce a complex series of cellular events in the DG one day after cessation of partial rapid kindling stimulation consisting (in comparison to control animals that were electrode implanted but unkindled), firstly, of an increase in the number of postmitotic BrdU labeled cells, and secondly, an increase in the number of DCX labeled cells, mainly in subgranular zone. Ultrastructural changes were examined using qualitative electron microscope analysis and 3-D reconstructions of both dendritic spines and postsynaptic densities. Typical features of kindling in comparison to control tissue included translocation of mitochondria to the base of the dendritic spine stalks; a migration of multivesicular bodies into mushroom dendritic spines, and most notably formation of "giant" spinules originating from the head of the spines of DG neurons. These morphological alterations arise at seizure stages 2-3 (focal seizures) in the absence of signs of the severe generalized seizures that are generally recognized as potentially harmful for neuronal cells. We suggest that an increase in ongoing neurogenesis, reactive astrogliosis and dendritic spine reorganization in the DG is the crucial step in the chain of events leading to the progressive development of seizure susceptibility in hippocampal circuits.


Assuntos
Astrócitos/patologia , Giro Denteado/patologia , Excitação Neurológica , Neurônios/patologia , Sinapses/patologia , Animais , Bromodesoxiuridina , Proliferação de Células , Espinhas Dendríticas/patologia , Giro Denteado/metabolismo , Giro Denteado/fisiopatologia , Proteínas do Domínio Duplacortina , Proteína Duplacortina , Eletroencefalografia , Proteína Glial Fibrilar Ácida/metabolismo , Gliose , Indicadores e Reagentes , Masculino , Proteínas Associadas aos Microtúbulos/metabolismo , Neuropeptídeos/metabolismo , Ratos , Ratos Wistar , Convulsões/metabolismo , Convulsões/patologia , Convulsões/fisiopatologia
10.
Biofizika ; 53(5): 879-85, 2008.
Artigo em Russo | MEDLINE | ID: mdl-18954019

RESUMO

Male rats were irradiated by a Korobkov photon light-emitting diode matrix with a maximum irradiation at 612 nm every day 1 h per day for 13 days. After a course of irradiation, the rhythmoinotropic characteristics of the cardiac muscle significantly improved. Exposure to photon radiation initiated an active rearrangement in myocytes as shown by a morphological analysis. Considerable changes were found in the structure of sarcoplasmic reticulum (SR); the area of SR profiles increased more than twofold compared to control. This suggests a proportional increase in the ability of SR to absorb calcium, due to both an increase in its buffer capacity and possibly, an improved functioning of Ca2+ ATPase of the reticulum. Probably, the photon therapy leads to the normalization of calcium homeostasis in myocytes and improvement of the characteristics of the cardiac muscle contraction-relaxation cycle. Furthermore, changes in the proportions of the myocardium capillaries (increased by 75% compared to control; p < 0.001) and the area of mitochondrial profiles of myocytes (increased by 13%; p < 0.05) were observed, which lead to more active metabolic processes and a rise in energy potential in myocardial cells after photon radiation treatment.


Assuntos
Contração Miocárdica/efeitos da radiação , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Fótons , Retículo Sarcoplasmático/metabolismo , Absorção/efeitos da radiação , Animais , Cálcio/metabolismo , ATPases Transportadoras de Cálcio/metabolismo , Circulação Coronária/efeitos da radiação , Feminino , Miocárdio/ultraestrutura , Miócitos Cardíacos/ultraestrutura , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Retículo Sarcoplasmático/ultraestrutura , Fatores de Tempo
11.
Biofizika ; 52(3): 565-71, 2007.
Artigo em Russo | MEDLINE | ID: mdl-17633550

RESUMO

The conditions of the protein-synthesizing system in neurons of the hippocampus (areas CA1 and C A3) and of the cortex (sensomotor region) in rats subjected to y-irradiation at a dose of 8 Gy under hypothermia (16 - 18 degrees C) and hypoxia-hypercapnia were investigated by fluorescent and electron microscopy. Under hypothermia, the protein-synthesizing system was shown to be damaged to a lesser degree and to be restored faster in comparison with similar neurons in rats irradiated at room temperature. In rats irradiated under hypothermia, the rRNA biogenesis and the protein-synthesizing activity of polyribosomes were restored in two days. The protective influence of hypothermia did not spread to changes in membrane structures (endoplasmic reticulum and Golgy apparatus); i.e., a partial loss of integrity and possible transformation of their structure caused by the irradiation and the restoration of these structures occurred at a lower rate.


Assuntos
Encéfalo/efeitos da radiação , Hipotermia Induzida , Neurônios/efeitos da radiação , Lesões por Radiação/prevenção & controle , Animais , Encéfalo/ultraestrutura , Masculino , Microscopia Eletrônica , Microscopia de Fluorescência , Neurônios/metabolismo , Neurônios/ultraestrutura , Biossíntese de Proteínas/efeitos da radiação , Lesões por Radiação/patologia , Ratos , Ratos Wistar
14.
Biofizika ; 51(2): 316-23, 2006.
Artigo em Russo | MEDLINE | ID: mdl-16637340

RESUMO

It was shown by fluorescent and electron microscopy that the physiological state of ground squirrels subjected to ionizing radiation at different phases of the torpor-normothermia cycle plays a determining role in the alteration of the conditions of the protein-synthesizing system in neurons of hippocampus fields CA1 and CA3 and sensomotor area of the brain. In ground squirrels irradiated under normothermia, the neurons were less radioresistant and restored slower compared with torpor animal cells, the distinctions being most expressed in CA1 field neurons. The effect of irradiation was minimum during the entrance into torpor and maximum during arousal. It was supposed that the inhibition of protein synthesis in the latter case occurred at the elongation stage when heavy polyribosomes were formed in neuron cytoplasm.


Assuntos
Raios gama , Hibernação/efeitos da radiação , Hipocampo/metabolismo , Neurônios/metabolismo , Biossíntese de Proteínas/efeitos da radiação , Roedores/metabolismo , Animais , Citoplasma/metabolismo , Citoplasma/ultraestrutura , Hipocampo/ultraestrutura , Neurônios/ultraestrutura , Polirribossomos/metabolismo , Polirribossomos/ultraestrutura
15.
Radiats Biol Radioecol ; 46(6): 706-12, 2006.
Artigo em Russo | MEDLINE | ID: mdl-17323699

RESUMO

The cooling of Wistar rats up to 15-19 degrees C under a condition hypoxia-hypercapnia increased the radioresistance with a dose reduction factor (DRF) of 1.4. To elucidate the mechanisms of hypothermia radioprotective effect was evaluated the functional state of rat neocortex using a electroencephalogram (EEG) as well as was studied the lipid composition of neocortex under the conditions of both normothermia and hypothermia. At 19-20 degrees C the activity within a wide range of frequencies in EEG was suppressed; the nonregular slow waves were recorded against a background of "silence". The reduction of EEG spectrum with increasing temperature began with the low frequencies. At 26-28 egresC the contribution of theta-rhythm (an indicator of brain activity level) in EEG reaches the normothermia value, from this point the rat brain starts to functionate as a whole system. At normothermia the similarity of neocortex lipid composition in nonhibernators (rats) and hibernators (ground squirrels) mammalians was noted. The difference is only in a higher content of phosphatidylinositol in rats. Rats falling into hypothermia state as well as ground squirrels into torpor is followed by a decrease of cholesterol content and the absence of significant changes of the phospholipid composition in neocortex tissues.


Assuntos
Hipotermia Induzida , Tolerância a Radiação/fisiologia , Animais , Temperatura Corporal , Encéfalo/fisiologia , Colesterol/metabolismo , Relação Dose-Resposta à Radiação , Eletroencefalografia , Frequência Cardíaca , Hibernação , Lipídeos/análise , Masculino , Neocórtex/metabolismo , Ratos , Ratos Wistar , Ritmo Teta , Raios X
16.
Eur J Neurosci ; 21(12): 3368-78, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16026474

RESUMO

Examination of the morphological correlates of long-term potentiation (LTP) in the hippocampus requires the analysis of both the presynaptic and postsynaptic elements. However, ultrastructural measurements of synapses and dendritic spines following LTP induced via tetanic stimulation presents the difficulty that not all synapses examined are necessarily activated. To overcome this limitation, and to ensure that a very large proportion of the synapses and spines examined have been potentiated, we induced LTP in acute hippocampal slices of adult mice by addition of tetraethylammonium (TEA) to a modified CSF containing an elevated concentration of Ca(2+) and no Mg(+). Quantitative electron microscope morphometric analyses and three-dimensional (3-D) reconstructions of both dendritic spines and postsynaptic densities (PSDs) in CA1 stratum radiatum were made on serial ultrathin sections. One hour after chemical LTP induction the proportion of macular (unperforated) synapses decreased (50%) whilst the number of synapses with simple perforated and complex PSDs (nonmacular) increased significantly (17%), without significant changes in volume and surface area of the PSD. In addition, the surface area of mushroom spines increased significantly (13%) whilst there were no volume differences in either mushroom or thin spines, or in surface area of thin spines. CA1 stratum radiatum contained multiple-synapse en passant axons as well as multiple-synapse spines, which were unaffected by chemical LTP. Our results suggest that chemical LTP induces active dendritic spine remodelling and correlates with a change in the weight and strength of synaptic transmission as shown by the increase in the proportion of nonmacular synapses.


Assuntos
Espinhas Dendríticas/efeitos dos fármacos , Hipocampo/citologia , Hipocampo/fisiologia , Potenciação de Longa Duração/efeitos dos fármacos , Bloqueadores dos Canais de Potássio/farmacologia , Sinapses/efeitos dos fármacos , Tetraetilamônio/farmacologia , Animais , Espinhas Dendríticas/ultraestrutura , Estimulação Elétrica/métodos , Técnicas In Vitro , Potenciação de Longa Duração/efeitos da radiação , Camundongos , Microscopia Eletrônica de Transmissão/métodos , Modelos Neurológicos , Plasticidade Neuronal/efeitos dos fármacos , Plasticidade Neuronal/fisiologia , Estimulação Química , Sinapses/classificação , Sinapses/ultraestrutura , Transmissão Sináptica/fisiologia
17.
Neuroscience ; 131(1): 43-54, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15680690

RESUMO

Chronic stress and spatial training have been proposed to affect hippocampal structure and function in opposite ways. Previous morphological studies that addressed structural changes after chronic restraint stress and spatial training were based on two-dimensional morphometry which does not allow a complete morphometric characterisation of synaptic features. Here, for the first time in such studies, we examined these issues by using three-dimensional (3-D) reconstructions of electron microscope images taken from thorny excrescences of hippocampal CA3 pyramidal cells. Ultrastructural alterations in postsynaptic densities (PSDs) of thorny excrescences receiving input from mossy fibre boutons were also determined, as were changes in numbers of multivesicular bodies (endosome-like structures) within thorny excrescences and dendrites. Quantitative 3-D data demonstrated retraction of thorny excrescences after chronic restraint stress which was reversed after water maze training, whilst water maze training alone increased thorny excrescence volume and number of thorns per thorny excrescence. PSD surface area was unaffected by restraint stress but water maze training increased both number and area of PSDs per thorny excrescence. In restrained rats that were water maze trained PSD volume and surface area increased significantly. The proportion of perforated PSDs almost doubled after water maze training and restraint stress. Numbers of endosome-like structures in thorny excrescences decreased after restraint stress and increased after water maze training. These findings demonstrate that circuits involving contacts between mossy fibre terminals and CA3 pyramidal cells at stratum lucidum level are affected conversely by water maze training and chronic stress, confirming the remarkable plasticity of CA3 dendrites. They provide a clear illustration of the structural modifications that occur after life experiences noted for their different impact on hippocampal function.


Assuntos
Hipocampo/anatomia & histologia , Hipocampo/fisiopatologia , Aprendizagem em Labirinto/fisiologia , Células Piramidais/fisiologia , Estresse Psicológico , Sinapses/fisiologia , Sinapses/ultraestrutura , Animais , Dendritos/ultraestrutura , Modelos Animais de Doenças , Células Piramidais/ultraestrutura , Ratos , Valores de Referência , Restrição Física
18.
Artigo em Russo | MEDLINE | ID: mdl-15069820

RESUMO

The article reviews the literature data and results obtained by the authors concerning synaptic plasticity and remodeling of synaptic organelles in the central nervous system. Modern techniques of laser scanning confocal microscopy and serial thin sectioning for in vivo and in vitro studies of dendritic spines including a correlation between morphological changes and synaptic transmission efficiency are discussed, particularly, in relation to long-term potentiation. Organization of different types of dendritic spines and involvement of filopodia in spine genesis are examined. Significance of serial ultrathin sections for unbiased quantitative stereological analysis and three-dimensional reconstructions is discussed. The contact of one dendritic spine with two presynaptic boutons (multiple synapses) on both CA1 mushroom dendritic spines is discussed. The analyzed findings suggest new ideas for organization and functioning of synapses.


Assuntos
Dendritos/ultraestrutura , Hipocampo/anatomia & histologia , Imageamento Tridimensional , Sinapses/ultraestrutura , Animais , Ratos , Sciuridae
19.
Arch Fam Med ; 2(4): 425-8, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8130922

RESUMO

Political and economic unrest in the former Soviet Union has been associated with an influx of refugees to the United States. The medical staff at our health maintenance organization perceived health care provision to the Soviet refugees as a goodwill opportunity, but soon realized that providing health care to this subpopulation of patients was very difficult. This was often related to cross-cultural differences regarding disclosure of medical information to the patient, acute care provision, and payment systems. Immigrants' expectations of US medicine are incredibly high. The interpreter plays a key role in facilitating communication between the health care team and the immigrant, yet the use of an interpreter has several inherent problems. Recognition of the problems and knowledge of the cross-cultural differences will likely improve rapport between health care personnel and immigrants.


Assuntos
Barreiras de Comunicação , Comparação Transcultural , Emigração e Imigração , Relações Médico-Paciente , Revelação da Verdade , Atenção à Saúde , Sistemas Pré-Pagos de Saúde , New York , U.R.S.S./etnologia
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