Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 65
Filtrar
Más filtros












Base de datos
Intervalo de año de publicación
1.
Artículo en Inglés | MEDLINE | ID: mdl-38963083

RESUMEN

Reports from recent years provide compelling evidence about the structure and the existence of functional topography in the cerebellum. However, most of them focused on the motor functions of the cerebellum. Recent studies suggest the involvement of the posterior lobe of the cerebellum in the context of neurodegenerative and cognitive disorders. The pathophysiology of these diseases is not sufficiently understood, and recent studies indicate that it could also affect additional subregions of the cerebellum. Anatomical and clinical studies, combined with neuroimaging, provide new ways of thinking about the organization and functioning of the cerebellum. This review summarizes knowledge about the topography and functions of the cerebellum, and focuses on its anatomical and functional contributions to the development of neurological diseases.

2.
Artículo en Inglés | MEDLINE | ID: mdl-38963084

RESUMEN

BACKGROUND: Typically, the anterior thoracic wall musculature is composed of the pectoralis major and pectoralis minor. Embryologically, these two muscles are originated from a common pectoral muscle mass; therefore, disruption of the normal development and differentiation could give rise to an aberrant or accessory muscle. The main aim of this study is to demonstrate and classify the accessory muscles of the pectoralis region in human fetuses. MATERIAL AND METHODS: Fifty spontaneously aborted human fetuses (25 male and 25 female, 100 sides) aged 18-38 weeks of gestation at death, and fixed in 10% formalin solution were examined. Following parental approval, the fetuses were donated to the Medical University anatomy program. The pectoralis major and minor muscle's morphology, the possible occurrence of accessory muscles of pectoral region and its morphology, their origins, and insertions, as well as the morphometric details, were assessed. RESULTS: The pectoralis major and minor were bilaterally found in all fetuses (100 cases). The accessory muscles of pectoral region were found in 16 cases (16%), and four types were differentiated. The Pectoralis Quartus muscle was the most common type of accessory muscles found in this study and occurred in 8 cases. The axillary arch muscle was observed in 3 cases. The chondrocoracoideus muscle was observed in 3 cases. The sternalis muscle occurred in 2 cases, and one of them was bifurcated. CONCLUSIONS: The thoracic region is characterized by a large amount of morphological variations, which are observed not only in adult population, but also among human fetuses. The pectoralis quartus was the most frequent variation in this study. Accessory structures like sternalis muscle, chondrocoracoideus muscle, pectoralis quartus muscle, or axillary arch muscle may have clinical implications, and knowledge about them is very useful for clinicians, especially plastic surgeons, thoracic surgeons, and orthopedics.

3.
Ann Anat ; 254: 152264, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38593907

RESUMEN

BACKGROUND: The pectoralis minor muscle is located in the anterior thoracic wall. Typically, is constituted by a single belly originating from the 3rd to the 5th rib and inserted into the coracoid process near the origins of the biceps brachii shorth head and of the coracobrachialis muscle. The current study, on human fetuses, aims to detect all morphological muscle variants and to create a new classification system. MATERIAL AND METHODS: Classical dissection of the thoracic wall and the upper limb was bilaterally performed on 25 (13 male and 12 female) human formalin-fixed fetuses aged 18-38 weeks of gestation. The spontaneously aborted fetuses were donated after parental consent to the Medical University anatomy program. The pectoralis minor muscle's morphology, the number of the muscle's bellies, their origins, and insertions, as well as the morphometric details of each belly of the pectoralis minor, were assessed. RESULTS: The pectoralis minor was bilaterally found in all fetuses (50 cases). Three types of muscle were identified based on the number of muscle bellies. In type, I (typical anatomy), were classified the cases with a single belly (in 66%). This type was divided into two subtypes (Ia and Ib). In the subtype Ia, the single belly had a typical course, and in Ib, a proximal attachment was characterized by two small bellies connecting together and creating one muscular mass. In type II, two bellies (24%), and in type III, three bellies (10%) were identified. CONCLUSIONS: Pectoralis minor is morphologically variable in the number of its bellies, its course, its origins, its insertions, and the location of its proximal attachments. The most common type (typical anatomy) was the type I represented by one belly. Other identified variants in the number of bellies by the present study may be hypothetically a result of prematurely terminated embryogenesis.


Asunto(s)
Feto , Músculos Pectorales , Humanos , Músculos Pectorales/anatomía & histología , Femenino , Feto/anatomía & histología , Masculino , Disección , Edad Gestacional
4.
Ann Anat ; 249: 152108, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37211259

RESUMEN

BACKGROUND: The pectoralis major muscle is located in the anterior chest wall. In most cases, it is divided into clavicular, sternal (sternocostal) and abdominal heads. The aim of this study is to demonstrate and classify the morphological variability of the pectoralis major muscles in human fetuses. MATERIAL AND METHODS: Classical anatomical dissection was performed on 35 human fetuses aged 18-38 weeks of gestation at death were examined. (17 female, and 18 male, 70 sides; fixed in 10% formalin solution). The fetuses were obtained from spontaneous abortion after informed consent of both parents and through deliberate donation to the Medical University anatomy program. Upon dissection, the following morphological features were assessed: the morphology of the pectoralis major, the possible occurrence of accessory heads, the possible absence of some head, and morphometric measurements of each head of the pectoralis major muscle. RESULTS: Five types of morphology (based on number of bellies) were observed in the fetuses. Type I was characterized by a single claviculosternal belly (10% of all samples). Type II comprised the clavicular and sternal heads (37.1%). Type III comprised three clavicular, sternal and abdominal heads (31.4%). Type IV (17.2%) was characterized by four muscle bellies and was divided into four subtypes. Type V (4.3%), was represented by five parts, and was divided into two subtypes. CONCLUSIONS: Due to its embryological development, the PM demonstrates great variability in the numbers of its parts. The most common type was the PM with two bellies, in line with previous studies which also distinguished only clavicular and sternal heads.


Asunto(s)
Clavícula , Músculos Pectorales , Humanos , Masculino , Femenino , Músculos Pectorales/anatomía & histología , Disección , Cadáver
5.
Metabolomics ; 19(4): 40, 2023 04 12.
Artículo en Inglés | MEDLINE | ID: mdl-37043024

RESUMEN

INTRODUCTION: The endocannabinoid system consists of different types of receptors, enzymes and endocannabinoids (ECs), which are involved in several physiological processes, but also play important role in the development and progression of central nervous system disorders. OBJECTIVES: The purpose of this study was to apply precise and sensitive methodology for monitoring of four ECs, namely anandamide (AEA), 2-arachidonoyl glycerol (2-AG), N-arachidonoyl dopamine (NADA), 2-arachidonyl glyceryl ether (2-AGe) in selected brain regions of female and male rats at different stages of development (young, adult and old). METHODS: Biocompatible solid-phase microextraction (SPME) probes were introduced into the intact (non-homogenized) brain structures for isolation of four ECs, and the extracts were subjected to LC-MS/MS analysis. Two chemometric approaches, namely hierarchical cluster analysis (HCA) and Principal Component Analysis (PCA) were applied to provide more information about the levels of 2-AG and AEA in different brain structures. RESULTS: 2-AG and AEA were extracted and could be quantified in each brain region; the level of 2-AG was significantly higher in comparison to the level of AEA. Two highly unstable ECs, NADA and 2-AGe, were captured by SPME probes from intact brain samples for the first time. CONCLUSION: SPME probes were able to isolate highly unstable endogenous compounds from intact tissue, and provided new tools for precise analysis of the level and distribution of ECs in different brain regions. Monitoring of ECs in brain samples is important not only in physiological conditions, but also may contribute to better understanding of the functioning of the endocannabinoid system in various disorders.


Asunto(s)
Endocannabinoides , Microextracción en Fase Sólida , Masculino , Ratas , Femenino , Animales , Cromatografía Liquida , Espectrometría de Masas en Tándem/métodos , Metabolómica , Encéfalo
6.
Clin Anat ; 35(4): 526-528, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35218594

RESUMEN

Human cadaveric donors are essential for research in the anatomical sciences. However, many research papers in the anatomical sciences often omit a statement regarding the ethical use of the donor cadavers or, as no current standardized versions exist, use language that is extremely varied. To rectify this issue, 22 editors-in-chief of anatomical journals, representing 17 different countries, developed standardized and simplified language that can be used by authors of studies that use human cadaveric tissues. The goal of these editor recommendations is to standardize the writing approach by which the ethical use of cadaveric donors is acknowledged in anatomical studies that use donor human cadavers. Such sections in anatomical papers will help elevate our discipline and promote standardized language use in others non anatomy journals and also other media outlets that use cadaveric tissues.


Asunto(s)
Anatomía , Donantes de Tejidos , Cadáver , Humanos
7.
Eur J Neurosci ; 54(3): 5173-5188, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34145920

RESUMEN

EBI2 receptor regulates the immune system, and in multiple, sclerosis is upregulated in the central nervous system infiltrating lymphocytes. In newborn EBI2-deficient mice, myelin development is delayed, and its persistent antagonism inhibits remyelination in chemically demyelinated organotypic cerebellar slices. We used the cuprizone model of multiple sclerosis to elucidate the role of central nervous system-expressed EBI2 in de- and remyelination. The wild-type and EBI2 knock-out mice were fed 0.2% cuprizone in chow for 5 weeks and allowed to recover on a normal diet for 2 weeks. The data showed less efficient recovery of myelin, attenuated oligodendrocyte loss, fewer astrocytes and increased total cholesterol levels in the EBI2 knock-out mice after recovery. Moreover, the wild-type mice upregulated EBI2 expression after recovery confirming the involvement of EBI2 signalling during recovery from demyelination in the cuprizone model. The pro-inflammatory cytokine levels were at comparable levels in the wild-type and EBI2 knock-out mice, with only minor differences in TNFα and IL1ß levels either at peak or during recovery. The neuroinflammatory signalling molecules, Abl1 kinase and NFКB1 (p105/p50) subunit, were significantly downregulated in the EBI2 knock-out mice at peak of disease. Immunohistochemical investigations of EBI2 receptor distribution in the central nervous system (CNS) cells in multiple sclerosis (MS) brain revealed strong expression of EBI2 in astrocytes and microglia inside the plaques implicating glia-expressed EBI2 in multiple sclerosis pathophysiology. Taken together, these findings demonstrate the involvement of EBI2 signalling in the recovery from demyelination rather than in demyelination and as such warrant further research into the role of EBI2 in remyelination.


Asunto(s)
Enfermedades Desmielinizantes , Esclerosis Múltiple , Remielinización , Animales , Cuprizona/toxicidad , Enfermedades Desmielinizantes/inducido químicamente , Modelos Animales de Enfermedad , Ratones , Ratones Endogámicos C57BL , Vaina de Mielina , Neuroglía , Oligodendroglía , Esclerosis
8.
Clin Anat ; 34(1): 2-4, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32808702

RESUMEN

Research within the anatomical sciences often relies on human cadaveric tissues. Without the good will of these donors who allow us to use their bodies to push forward our anatomical knowledge, most human anatomical research would come to a standstill. However, many research papers omit an acknowledgement to the donor cadavers or, as no current standardized versions exist, use language that is extremely varied. To remedy this problem, 20 editors-in-chiefs from 17 anatomical journals joined together to put together official recommendations that can be used by authors when acknowledging the donor cadavers used in their studies. The goal of these recommendations is to standardize the writing approach by which donors are acknowledged in anatomical studies that use human cadaveric tissues. Such sections in anatomical papers will not only rightfully thank those who made the donation but might also encourage, motivate, and inspire future individuals to make such gifts for the betterment of the anatomical sciences and patient care.


Asunto(s)
Anatomía/educación , Cadáver , Publicaciones Periódicas como Asunto , Obtención de Tejidos y Órganos , Investigación Biomédica , Disección , Humanos
9.
Acta Neurobiol Exp (Wars) ; 80(3): 305-321, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32990288

RESUMEN

In humans, pyruvate dehydrogenase complex (PDC) deficiency impairs brain energy metabolism by reducing the availability of the functional acetyl­CoA pool. This "hypometabolic defect" results in congenital lactic acidosis and abnormalities of brain morphology and function, ranging from mild ataxia to profound psychomotor retardation. Our previous study showed reduction in total cell number and dendritic arbors in the cerebellar Purkinje cells in systemic PDC­deficient mice. Phenylbutyrate has been shown to increase PDC activity in cultured fibroblasts from PDC­deficient patients. Hence, we investigated the effects of postnatal (days 2­35) phenylbutyrate administration on the cerebellar Purkinje cell population in PDC­deficient female mice. Histological analyses of different regions of cerebellar cortex from the brain­specific PDC­deficient saline­injected mice revealed statistically significant reduction in the Purkinje cell density and increased cell size of the individual Purkinje cell soma compared to control PDC­normal, saline­injected group. Administration of phenylbutyrate to control mice did not cause significant changes in the Purkinje cell density and cell size in the studied regions. In contrast, administration of phenylbutyrate variably lessened the ill effects of PDC deficiency on Purkinje cell populations in different areas of the cerebellum. Our results lend further support for the possible use of phenylbutyrate as a potential treatment for PDC deficiency.


Asunto(s)
Encéfalo/efectos de los fármacos , Neuronas/efectos de los fármacos , Fenilbutiratos/farmacología , Células de Purkinje/efectos de los fármacos , Animales , Corteza Cerebelosa/efectos de los fármacos , Cerebelo/efectos de los fármacos , Modelos Animales de Enfermedad , Ratones Transgénicos , Fenilbutiratos/metabolismo , Células de Purkinje/citología
10.
Transl Stroke Res ; 11(4): 553-579, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-31701356

RESUMEN

Cerebral stroke, which is one of the most frequent causes of mortality and leading cause of disability in developed countries, often leads to devastating and irreversible brain damage. Neurological and neuroradiological diagnosis of stroke, especially in its acute phase, is frequently uncertain or inconclusive. This results in difficulties in identification of patients with poor prognosis or being at high risk for complications. It also makes difficult identification of these stroke patients who could benefit from more aggressive therapies. In contrary to the cardiovascular disease, no single biomarker is available for the ischemic stroke, addressing the abovementioned issues. This justifies the need for identifying of effective diagnostic measures characterized by high specificity and sensitivity. One of the promising avenues in this area is studies on the panels of biomarkers characteristic for processes which occur in different types and phases of ischemic stroke and represent all morphological constituents of the brains' neurovascular unit (NVU). In this review, we present the current state of knowledge concerning already-used or potentially applicable biomarkers of the ischemic stroke. We also discuss the perspectives for identification of biomarkers representative for different types and phases of the ischemic stroke, as well as for different constituents of NVU, which concentration levels correlate with extent of brain damage and patients' neurological status. Finally, a critical analysis of perspectives on further improvement of the ischemic stroke diagnosis is presented.


Asunto(s)
Isquemia Encefálica/diagnóstico , Accidente Cerebrovascular Isquémico/diagnóstico , Accidente Cerebrovascular Isquémico/fisiopatología , Acoplamiento Neurovascular , Animales , Biomarcadores/metabolismo , Encéfalo/irrigación sanguínea , Encéfalo/metabolismo , Encéfalo/fisiopatología , Isquemia Encefálica/complicaciones , Isquemia Encefálica/metabolismo , Isquemia Encefálica/fisiopatología , Encefalitis/complicaciones , Encefalitis/metabolismo , Humanos , Accidente Cerebrovascular Isquémico/complicaciones , Accidente Cerebrovascular Isquémico/metabolismo , Investigación Biomédica Traslacional
11.
Molecules ; 24(10)2019 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-31108977

RESUMEN

This paper aims to present computer modeling of synaptic plasticity and memory in the CA3-CA1 hippocampal formation microcircuit. The computer simulations showed a comparison of a pathological model in which Alzheimer's disease (AD) was simulated by synaptic degradation in the hippocampus and control model (healthy) of CA3-CA1 networks with modification of weights for the memory. There were statistically higher spike values of both CA1 and CA3 pyramidal cells in the control model than in the pathological model (p = 0.0042 for CA1 and p = 0.0033 for CA3). A similar outcome was achieved for frequency (p = 0.0002 for CA1 and p = 0.0001 for CA3). The entropy of pyramidal cells of the healthy CA3 network seemed to be significantly higher than that of AD (p = 0.0304). We need to study a lot of physiological parameters and their combinations of the CA3-CA1 hippocampal formation microcircuit to understand AD. High statistically correlations were obtained between memory, spikes and synaptic deletion in both CA1 and CA3 cells.


Asunto(s)
Enfermedad de Alzheimer/psicología , Región CA1 Hipocampal/fisiopatología , Región CA3 Hipocampal/fisiopatología , Enfermedad de Alzheimer/fisiopatología , Simulación por Computador , Entropía , Humanos , Memoria , Plasticidad Neuronal , Células Piramidales/fisiología
12.
Entropy (Basel) ; 21(4)2019 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-33267122

RESUMEN

The aim of the study was to compare the computer model of synaptic breakdown in an Alzheimer's disease-like pathology in the dentate gyrus (DG), CA3 and CA1 regions of the hippocampus with a control model using neuronal parameters and methods describing the complexity of the system, such as the correlative dimension, Shannon entropy and positive maximal Lyapunov exponent. The model of synaptic breakdown (from 13% to 50%) in the hippocampus modeling the dynamics of an Alzheimer's disease-like pathology was simulated. Modeling consisted in turning off one after the other EC2 connections and connections from the dentate gyrus on the CA3 pyramidal neurons. The pathological model of synaptic disintegration was compared to a control. The larger synaptic breakdown was associated with a statistically significant decrease in the number of spikes (R = -0.79, P < 0.001), spikes per burst (R = -0.76, P < 0.001) and burst duration (R = -0.83, P < 0.001) and an increase in the inter-burst interval (R = 0.85, P < 0.001) in DG-CA3-CA1. The positive maximal Lyapunov exponent in the control model was negative, but in the pathological model had a positive value of DG-CA3-CA1. A statistically significant decrease of Shannon entropy with the direction of information flow DG->CA3->CA1 (R = -0.79, P < 0.001) in the pathological model and a statistically significant increase with greater synaptic breakdown (R = 0.24, P < 0.05) of the CA3-CA1 region was obtained. The reduction of entropy transfer for DG->CA3 at the level of synaptic breakdown of 35% was 35%, compared with the control. Entropy transfer for CA3->CA1 at the level of synaptic breakdown of 35% increased to 95% relative to the control. The synaptic breakdown model in an Alzheimer's disease-like pathology in DG-CA3-CA1 exhibits chaotic features as opposed to the control. Synaptic breakdown in which an increase of Shannon entropy is observed indicates an irreversible process of Alzheimer's disease. The increase in synapse loss resulted in decreased information flow and entropy transfer in DG->CA3, and at the same time a strong increase in CA3->CA1.

13.
Entropy (Basel) ; 21(6)2019 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-33267301

RESUMEN

The aim of this study was to evaluate the possibility of the gamma oscillation function (40-130 Hz) to reduce Alzheimer's disease related pathology in a computer model of the hippocampal network dentate gyrus, CA3, and CA1 (DG-CA3-CA1) regions. Methods: Computer simulations were made for a pathological model in which Alzheimer's disease was simulated by synaptic degradation in the hippocampus. Pathology modeling was based on sequentially turning off the connections with entorhinal cortex layer 2 (EC2) and the dentate gyrus on CA3 pyramidal neurons. Gamma induction modeling consisted of simulating the oscillation provided by the septo-hippocampal pathway with band frequencies from 40-130 Hz. Pathological models with and without gamma induction were compared with a control. Results: In the hippocampal regions of DG, CA3, and CA1, and jointly DG-CA3-CA1 and CA3-CA1, gamma induction resulted in a statistically significant improvement in terms of increased numbers of spikes, spikes per burst, and burst duration as compared with the model simulating Alzheimer's disease (AD). The positive maximal Lyapunov exponent was negative in both the control model and the one with gamma induction as opposed to the pathological model where it was positive within the DG-CA3-CA1 region. Gamma induction resulted in decreased transfer entropy in accordance with the information flow in DG → CA3 and CA3 → CA1. Conclusions: The results of simulation studies show that inducing gamma oscillations in the hippocampus may reduce Alzheimer's disease related pathology. Pathologically higher transfer entropy values after gamma induction returned to values comparable to the control model.

14.
J Chem Neuroanat ; 88: 1-12, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29100904

RESUMEN

Coffee and nicotine consumption are frequently combined, indicating possible intensifying effect of caffeine on smoking behavior, although neurobiological background of this phenomenon remains unknown. We aimed at determining the effect of caffeine and nicotine, applied separately or simultaneously, on activation of six structures of the brain reward system: nucleus accumbens (NAc), ventral tegmental area (VTA), amygdala (Amg), hippocampus (Hip), medial prefrontal cortex (mPfr) and dorsal striatum (CdP) in the adult male Wistar rats. Activation of two transcription factors, the phosphorylated form of cyclic AMP-response element binding protein (pCREB) and DeltaFosB (ΔFosB) was assessed by immunohistochemistry after multiple-dose five-days psychostimulants administration followed by 20min and 24h survival, respectively. Nicotine evoked the highest increase of pCREB-immunoreactivity (-ir) in NAc, while caffeine exerted the weakest effect in mPfr and CdP. Nicotine/caffeine co-administration resulted in decrease of pCREB-ir in NAc and increase in Amg, compared with the effect of each psychostimulant used separately. Nicotine was the strongest psychostimulant activating ΔFosB-ir in Amg, whereas caffeine - in Hip. Nicotine/caffeine-exerted effect upon ΔFosB-ir in Amg was weaker, whereas in mPfr stronger, than nicotine-evoked effect in these structures. In summary, pCREB and ΔFosB activation is dependent on the type of stimulus, brain structure and functional context. Activation of both transcription factors is responsible for caffeine's modifying effect upon nicotine-related behaviors and must be taken into account while quitting cigarette smoking.


Asunto(s)
Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Cafeína/farmacología , Estimulantes del Sistema Nervioso Central/farmacología , Nicotina/farmacología , Animales , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Masculino , Agonistas Nicotínicos/farmacología , Proteínas Proto-Oncogénicas c-fos/metabolismo , Ratas , Ratas Wistar , Recompensa
15.
Cell Mol Neurobiol ; 38(3): 579-593, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28623429

RESUMEN

Brain-derived neurotrophic factor (BDNF) is one of the most widely distributed and extensively studied neurotrophins in the mammalian brain. Among its prominent functions, one can mention control of neuronal and glial development, neuroprotection, and modulation of both short- and long-lasting synaptic interactions, which are critical for cognition and memory. A wide spectrum of processes are controlled by BDNF, and the sometimes contradictory effects of its action can be explained based on its specific pattern of synthesis, comprising several intermediate biologically active isoforms that bind to different types of receptor, triggering several signaling pathways. The functions of BDNF must be discussed in close relation to the stage of brain development, the different cellular components of nervous tissue, as well as the molecular mechanisms of signal transduction activated under physiological and pathological conditions. In this review, we briefly summarize the current state of knowledge regarding the impact of BDNF on regulation of neurophysiological processes. The importance of BDNF for future studies aimed at disclosing mechanisms of activation of signaling pathways, neuro- and gliogenesis, as well as synaptic plasticity is highlighted.


Asunto(s)
Factor Neurotrófico Derivado del Encéfalo/metabolismo , Encéfalo/metabolismo , Plasticidad Neuronal/fisiología , Transducción de Señal/fisiología , Sinapsis/metabolismo , Animales , Encéfalo/efectos de los fármacos , Factor Neurotrófico Derivado del Encéfalo/farmacología , Humanos , Plasticidad Neuronal/efectos de los fármacos , Receptor trkB/metabolismo , Transducción de Señal/efectos de los fármacos , Sinapsis/efectos de los fármacos
16.
Folia Neuropathol ; 56(4): 321-327, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30786669

RESUMEN

We report here the light and electron microscopic neuropathology of the 139A-H strain of scrapie passaged in Syrian golden hamsters. The general neuropathological picture consisted of the spongiform change and severe astrocytic gliosis. The topography of prion protein (PrP) was variable, the highest signal was observed in the CA2-molecular layer, CA1-pyramidal and entorhinal cortex. The electron microscopy consisted of: 1. Spongiform vacuoles - these are always membrane bound and contain secondary vacuoles (i.e. membrane-bound compartments or vesicles within vacuoles) and curled membraned fragments. 2. Tubulovesicular structures (TVS) - these are vesicular structures of approximate 27 nm in diameter within neuronal processes - i.e. axonal terminal or dendrites. TVS are smaller and of higher electron density than synaptic vesicles. The significance of TVS remains unknown. 3. Dystrophic neurites. Dendrites or axonal preterminals and terminals filled with electron-dense bodies, including small autophagic vacuoles. 4. Apoptotic cell nuclei. 5. "Whorls", concentric arrays of membranes were visible. A significance of those structures is unknown.


Asunto(s)
Axones/patología , Encéfalo/patología , Dendritas/patología , Neuronas/patología , Animales , Encéfalo/ultraestructura , Cricetinae , Mesocricetus , Microscopía Electrónica de Transmisión/métodos , Enfermedades del Sistema Nervioso/patología , Neuronas/metabolismo , Vesículas Sinápticas/patología
17.
Transl Neurosci ; 8: 70-75, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28828183

RESUMEN

Clinicians often rely on selected small molecular compounds from body fluids for the detection, screening or monitoring of numerous life-threatening diseases. Among others, important monoamines - biogenic amines (BAs) - and their metabolites serve as sensitive biomarkers to study the progression or even early detection of on-going brain pathologies or tumors of neuroendocrine origins. Undertaking the task to optimize a reliable method for the simultaneous analysis of the most relevant BAs in biological matrices is of utmost importance for scientists. Hydrophilic interaction liquid chromatography (HILIC) with mass spectrometry (MS) detection provides a specific and sensitive technique for the separation and assessment of several neurotransmitter concentrations in body fluids (blood, urine, tissues). The present study was focused on the optimization of a straightforward, sensitive and reliable method for the simultaneous analysis of the ten most important BAs and their acidic metabolites from homogenates of rat brain tissues by use of HILIC-MS. Here, we present the optimized experimental workflow in terms of sample preparation, buffer compositions, HILIC and MS settings and data analysis. The presented method is reliable, straightforward and sensitive. Our method permits the unbiased, qualitative and quantitative determination of several BAs and their metabolites simultaneously. The optimized method was applied to the analysis of rat brain tissue samples from healthy hemispheres or those with induced transient ischemic attack (TIA). The undertaken pilot study demonstrated that the proposed approach could be applied to reveal the perturbation in neurotransmitters concentration after TIA in rat brains.

18.
Acta Neurobiol Exp (Wars) ; 77(1): 68-76, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28379217

RESUMEN

The way hippocampal neurons function during stress in old age (critical times of life) is dependent on brain derived neurotrophin factor (BDNF). This study examined the influence of acute and chronic forced swim (FS) or high-light open field (HL­OF) stimulation on the density of BDNF immunoreactive (ir) neurons in the hippocampal pyramidal layers of CA1, CA2, CA3 regions and the granular layer of dentate gyrus (DG) in old (postnatal day 720; P720) Wistar Han rats. Our data showed that in comparison with non-stressed rats, acute FS caused a significant increase in the density of BDNF-ir neurons in CA2 and CA3, while acute HL-OF led to an increase in this factor in all hippocampal subfields with the exception of DG. However, the density of BDNF-ir cells remained unchanged after exposure to chronic FS or HL­OF in the hippocampal regions in relation to the control rats. These results indicate that acute FS or HL-OF proved to be a stressor that induces an increase in the density of BDNF-ir pyramidal neurons, which was probably connected with up-regulation of HPA axis activity and short­time memory processing of the stressful situation. Moreover, as far as the influence on BDNF-ir cells in hippocampus is concerned, chronic FS or HL-OF was not an aggravating factor for rats in the ontogenetic periods studied.


Asunto(s)
Envejecimiento , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Regulación de la Expresión Génica/fisiología , Hipocampo/metabolismo , Estrés Psicológico/patología , Factores de Edad , Análisis de Varianza , Animales , Modelos Animales de Enfermedad , Conducta Exploratoria , Hipocampo/patología , Masculino , Neuronas/metabolismo , Ratas , Ratas Wistar , Natación/psicología
19.
Cell Biol Toxicol ; 33(6): 557-573, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28281027

RESUMEN

The incidence of malignant melanoma, the most aggressive skin cancer, is increasing constantly. Despite new targeted therapies, the prognosis for patients with metastatic disease remains poor. Thus, there is a need for new combinational treatments, and antineoplastic agents potentially valuable in this approach are inhibitors of the ubiquitin-proteasome system (UPS). In this work, we analyze the cytotoxicity mechanisms of proteasome inhibitors (MG-132, epoxomicin, and lactacystin) in a specific form of melanoma which does not synthesize melanin-the amelanotic melanoma (Ab cells). We found that the most cytotoxic of the compounds tested was epoxomicin. Caspase-9 activation as well as cytochrome C and AIF release from mitochondria indicated that exposure to epoxomicin induced the mitochondrial pathway of apoptosis. Epoxomicin treatment also resulted in accumulation of Bcl-2 family members-proapoptotic Noxa and antiapoptotic Mcl-1, which were postulated as the targets for bortezomib in melanoma. Inhibition of caspases by BAF revealed that cell death was partially caspase-independent. We observed no cell cycle arrest preceding the apoptosis of Ab cells, even though cdk inhibitors p21Cip1/Waf1 and p27Kip1 were up-regulated. The cell cycle was blocked only after inactivation of caspases by the pan-caspase inhibitor BAF. In summary, this is the first study exploring molecular mechanisms of cell death induced by epoxomicin in melanoma. We found that Ab cells died on the mitochondrial pathway of apoptosis and also partially by the caspase-independent way of death. Apoptosis induction was fast and efficient and was not preceded by cell cycle arrest.


Asunto(s)
Melanoma Amelanótico/tratamiento farmacológico , Melanoma Amelanótico/enzimología , Complejo de la Endopetidasa Proteasomal/metabolismo , Inhibidores de Proteasoma/farmacología , Neoplasias Cutáneas/tratamiento farmacológico , Neoplasias Cutáneas/enzimología , Animales , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Cricetinae , Masculino , Melanoma Amelanótico/patología , Mesocricetus , Neoplasias Cutáneas/patología
20.
J Chem Neuroanat ; 78: 57-64, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27565677

RESUMEN

It seems that age-dependent changes in stress response may be correlated with alterations in the hypothalamic brain derived neurotrophin factor (BDNF). Two hypothalamic nuclei, ie. paraventricular (PVN) and supraoptic (SON) are closely related to the stress response. Therefore, the aim of our study was to explore the influence of acute and chronic high-light open field (HL-OF) or forced swim (FS) stimulation on the density of BDNF immunoreactive (ir) neurons in the PVN and SON in adult (postnatal day 90; P90) and aged (P720) Wistar Han rats. Our data demonstrated that in comparison with non-stressed rats, neither acute nor chronic FS caused significant changes in the density of BDNF-ir neurons of PVN and SON in P90 or P720 rats. However, a significant increase in the density of BDNF-ir neurons in the SON of P90 and a decrease in the PVN of the P720 rats were noted after acute HL-OF. Despite the lack of change in the density of BDNF-ir neurons between P90 and P720 non-stressed and FS stressed rats, there was an age-dependent decrease in the BDNF-ir cells of HL-OF stressed rats, especially in the PVN. We may conclude that in terms of its influence on the BDNF-ir neurons in PVN and SON, acute HL-OF was the factor inducing changes in the density of BDNF-ir neurons in the hypothalamic nuclei of adult or aged rats. Furthermore, ageing involutional processes, which can impair hypothalamic-pituitary-adrenal axis functioning, may have been able to cause an age-related decrease in the BDNF-ir PVN and/or SON neurons in HL-OF stressed rats.


Asunto(s)
Envejecimiento/metabolismo , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Núcleo Hipotalámico Paraventricular/metabolismo , Estrés Fisiológico/fisiología , Estrés Psicológico/metabolismo , Núcleo Supraóptico/metabolismo , Factores de Edad , Animales , Sistema Hipotálamo-Hipofisario/metabolismo , Masculino , Neuronas/metabolismo , Sistema Hipófiso-Suprarrenal/metabolismo , Ratas , Ratas Wistar , Natación
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...