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1.
Psychiatr Danub ; 34(3): 497-505, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36256988

RESUMO

BACKGROUND: The aim of this study (ClinicalTrials.gov identifier: NCT03233958) was to provide further evidence on the effectiveness and safety of family/systemic constellation therapy, a widely used but rarely investigated form of brief group psychotherapy. SUBJECTS AND METHODS: Altogether, 102 individuals from the general population were followed up 1- and 6 months after their participation in the 2-day intervention. Indicators of general and problem-area-specific psychopathology, interpersonal quality of life, meaning in life, and general wellbeing were assessed. Both statistical and clinical significance were considered, and active surveillance of potential iatrogenic effects was also conducted. RESULTS: The data showed significant improvement post-intervention in the case of the vast majority of the 17 outcome variables. At 1-month follow-up, the magnitude of improvements was typically in the moderate range. The patterns were very similar at the 6-month follow-up, suggesting that most intervention benefits were sustained in the middle term. Sensitivity analyses showed no therapist effects across the three intervention providers. Analyses into clinical significance showed that the most reliable improvements occurred in relation to interpersonal quality of life and non-diagnosis-specific psychopathology, with approximately half of the participants showing reliable improvement. Iatrogenic effects were comparable - both in terms of frequency and severity - to those reported for other forms of psychotherapy. CONCLUSIONS: Findings of the present study point toward the safety and effectiveness of family constellation therapy in reducing a variety of psychopathological symptoms (e.g., depression and anxiety) and increasing general well-being. This effectiveness is especially remarkable when considering the brevity and cost-effectiveness of the intervention.


Assuntos
Terapia Cognitivo-Comportamental , Humanos , Qualidade de Vida , Transtornos de Ansiedade/terapia , Psicoterapia , Doença Iatrogênica
2.
Neurobiol Dis ; 151: 105252, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33418069

RESUMO

Galactic cosmic radiation (GCR), composed of highly energetic and fully ionized atomic nuclei, produces diverse deleterious effects on the body. In researching the neurological risks of GCR exposures, including during human spaceflight, various ground-based single-ion GCR irradiation paradigms induce differential disruptions of cellular activity and overall behavior. However, it remains less clear how irradiation comprising a mix of multiple ions, more accurately recapitulating the space GCR environment, impacts the central nervous system. We therefore examined how mixed-ion GCR irradiation (two similar 5-6 beam combinations of protons, helium, oxygen, silicon and iron ions) influenced neuronal connectivity, functional generation of activity within neural circuits and cognitive behavior in mice. In electrophysiological recordings we find that space-relevant doses of mixed-ion GCR preferentially alter hippocampal inhibitory neurotransmission and produce related disruptions in the local field potentials of hippocampal oscillations. Such underlying perturbation in hippocampal network activity correspond with perturbed learning, memory and anxiety behavior.


Assuntos
Radiação Cósmica/efeitos adversos , Hipocampo/efeitos da radiação , Transmissão Sináptica/efeitos da radiação , Animais , Comportamento Animal/efeitos da radiação , Disfunção Cognitiva/etiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL
3.
J Environ Manage ; 248: 109277, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31349125

RESUMO

The quasi-natural meandering type of alluvial rivers is quite unusual in Central European watersheds. The lack of extensive regulation allows such rivers to shift along their floodplain and cause erosion of natural and agricultural lands. Description of channel morphometric parameters over decadal timescales allows a better understanding of such river systems like Sajó River (Slovakia-Hungary) where no preliminary work is available regarding channel dynamics. In addition, to just describing the geomorphic processes, the environmental management implications of these meandering rivers need to be investigated as well. Thus, this study represents a bend-scale morphological analysis on the 124 km long section of the Sajó River in the Hungarian territory in eight different periods between 1952 and 2011. Archive aerial imagery, orthophotographs and topographical maps were organized into a database, then GIS-based analyses were performed to quantify the rate and extent of channel shifts, bend development and the area of erosion/accretion. On the bend scale, we have calculated several morphometric parameters (bend length, chord, amplitude, the radius of curvature) to quantify the evolutionary trajectory of reaches. Hydrological time series data were evaluated to reveal its possible role in the processes. Based on the available GIS-data of natural elements and anthropogenic intervention, we delineated 12 different reaches showing similar characteristics, from which six reaches were defined as natural. According to the morphometric parameters of the natural reaches, channel widths became narrower and the planform became more concentrated spatially in most of the reaches while the overall sinuosity of almost all natural reaches increased. Although artificial cutoffs mainly reduced the reach complexity, in some cases, they have accelerated the bend development downstream in the following few years. Erosion and accretion activity were higher in the periods when the discharge was higher than the effective discharge but its effect became less apparent in the second half of the investigated time period. By 1980, major artificial cutoffs and bank protection works were carried out that could have an impact in reducing the potential channel shifting. Based on our results, we propose a possible preservation and some modifications along the Hungarian part of the Sajó River reaches to be carried out by the local river management authorities. We conclude that this study provides a detailed demonstration of the Sajó River morphodymanics which can be used for further land planning to avoid harmful consequences of recent bank erosion processes not only along the Sajó River, but other similar rivers in Europe.


Assuntos
Agricultura , Rios , Europa (Continente) , Hungria , Eslováquia
4.
Inorg Chem ; 57(10): 6107-6117, 2018 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-29746106

RESUMO

Typically, the synthesis of radiometal-based radiopharmaceuticals is performed in buffered aqueous solutions. We found that the presence of organic solvents like ethanol increased the radiolabeling yields of [68Ga]Ga-DOTA (DOTA = 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacatic acid). In the present study, the effect of organic cosolvents [ethanol (EtOH), isopropyl alcohol, and acetonitrile] on the radiolabeling yields of the macrocyclic chelator DOTA with several trivalent radiometals (gallium-68, scandium-44, and lutetium-177) was systematically investigated. Various binary water (H2O)/organic solvent mixtures allowed the radiolabeling of DOTA at a significantly lower temperature than 95 °C, which is relevant for the labeling of sensitive biological molecules. Simultaneously, much lower amounts of the chelators were required. This strategy may have a fundamental impact on the formulation of trivalent radiometal-based radiopharmaceuticals. The equilibrium properties and formation kinetics of [M(DOTA)]- (MIII= GaIII, CeIII, EuIII, YIII, and LuIII) complexes were investigated in H2O/EtOH mixtures (up to 70 vol % EtOH). The protonation constants of DOTA were determined by pH potentiometry in H2O/EtOH mixtures (0-70 vol % EtOH, 0.15 M NaCl, 25 °C). The log K1H and log K2H values associated with protonation of the ring N atoms decreased with an increase of the EtOH content. The formation rates of [M(DOTA)]- complexes increase with an increase of the pH and [EtOH]. Complexation occurs through rapid formation of the diprotonated [M(H2DOTA)]+ intermediates, which are in equilibrium with the kinetically active monoprotonated [M(HDOTA)] intermediates. The rate-controlling step is deprotonation (and rearrangement) of the monoprotonated intermediate, which occurs through H2O (*M(HL) kH2O) and OH- (*M(HL) kOH) assisted reaction pathways. The rate constants are essentially independent of the EtOH concentration, but the M(HL) kH2O values increase from CeIII to LuIII. However, the log KM(HL)H protonation constants, analogous to the log KH2 value, decrease with increasing [EtOH], which increases the concentration of the monoprotonated M(HDOTA) intermediate and accelerates formation of the final complexes. The overall rates of complex formation calculated by the obtained rate constants at different EtOH concentrations show a trend similar to that of the complexation rates determined with the use of radioactive isotopes.

5.
Eur J Neurosci ; 45(4): 548-558, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27977063

RESUMO

The perisomatic region of principal neurons in cortical regions is innervated by three types of GABAergic interneuron, including parvalbumin-containing basket cells (PVBCs) and axo-axonic cells (AACs), as well as cholecystokinin and type 1 cannabinoid receptor-expressing basket cells (CCK/CB1BCs). These perisomatic inhibitory cell types can also be found in the basal nucleus of the amygdala, however, their output properties are largely unknown. Here, we performed whole-cell recordings in morphologically identified interneurons in slices prepared from transgenic mice, in which the GABAergic cells could be selectively targeted. Investigating the passive and active membrane properties of interneurons located within the basal amygdala revealed that the three interneuron types have distinct single-cell properties. For instance, the input resistance, spike rate, accommodation in discharge rate, or after-hyperpolarization width at the half maximal amplitude separated the three interneuron types. Furthermore, we performed paired recordings from interneurons and principal neurons to uncover the basic features of unitary inhibitory postsynaptic currents (uIPSCs). Although we found no difference in the magnitude of responses measured in the principal neurons, the uIPSCs originating from the distinct interneuron types differed in rise time, failure rate, latency, and short-term dynamics. Moreover, the asynchronous transmitter release induced by a train of action potentials was typical for the output synapses of CCK/CB1BCs. Our results suggest that, despite the similar uIPSC magnitudes originating from the three perisomatic inhibitory cell types, their distinct release properties together with the marked differences in their spiking characteristics may contribute to accomplish specific functions in amygdala network operation.


Assuntos
Tonsila do Cerebelo/fisiologia , Neurônios GABAérgicos/fisiologia , Potenciais Pós-Sinápticos Inibidores , Interneurônios/fisiologia , Potenciais de Ação , Tonsila do Cerebelo/citologia , Animais , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL
6.
J Neurosci ; 34(23): 7958-63, 2014 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-24899717

RESUMO

CB1 cannabinoid receptors (CB1) are located at axon terminals and effectively control synaptic communication and thereby circuit operation widespread in the CNS. Although it is partially uncovered how CB1 activation leads to the reduction of synaptic excitation, the mechanisms of the decrease of GABA release upon activation of these cannabinoid receptors remain elusive. To determine the mechanisms underlying the suppression of synaptic transmission by CB1 at GABAergic synapses, we recorded unitary IPSCs (uIPSCs) at cholecystokinin-expressing interneuron-pyramidal cell connections and imaged presynaptic [Ca(2+)] transients in mouse hippocampal slices. Our results reveal a power function with an exponent of 2.2 between the amplitude of uIPSCs and intrabouton [Ca(2+)]. Altering CB1 function by either increasing endocannabinoid production or removing its tonic activity allowed us to demonstrate that CB1 controls GABA release by inhibiting Ca(2+) entry into presynaptic axon terminals via N-type (Cav2.2) Ca(2+) channels. These results provide evidence for modulation of intrabouton Ca(2+) influx into GABAergic axon terminals by CB1, leading to the effective suppression of synaptic inhibition.


Assuntos
Cálcio/metabolismo , Terminações Pré-Sinápticas/metabolismo , Receptor CB1 de Canabinoide/metabolismo , Sinapses/fisiologia , Ácido gama-Aminobutírico/metabolismo , Animais , Animais Recém-Nascidos , Bloqueadores dos Canais de Cálcio/farmacologia , Colecistocinina/genética , Colecistocinina/farmacologia , Feminino , Hipocampo/citologia , Técnicas In Vitro , Potenciais Pós-Sinápticos Inibidores/efeitos dos fármacos , Potenciais Pós-Sinápticos Inibidores/fisiologia , Interneurônios/efeitos dos fármacos , Interneurônios/fisiologia , Proteínas Luminescentes/genética , Masculino , Camundongos , Camundongos Transgênicos , Piperidinas/farmacologia , Terminações Pré-Sinápticas/efeitos dos fármacos , Pirazóis/farmacologia , Sinapses/efeitos dos fármacos , ômega-Conotoxina GVIA/farmacologia
7.
Orv Hetil ; 156(13): 516-20, 2015 Mar 29.
Artigo em Húngaro | MEDLINE | ID: mdl-25796279

RESUMO

Among their beneficial effects, non-steroidal anti-inflammatory drugs may also exert several side effects which depend on the dosage and the type of these medications. The most frequent gastrointestinal side effects usually develop shortly after the beginning of their administration, but others such as cardiovascular interactions (which are present much less frequently than gastrointestinal side effects) can also occur after the beginning of drug administration without a latency period. For a long-term treatment, non-steroidal anti-inflammatory drugs are most frequently used in the elderly population where patients typically have high cardiovascular risk and take other medicines, e.g. low dose acetylsalicylic acid that can interact with non-steroidal anti-inflammatory drugs; in this aspect diclofenac may cause less side effects. In this review, the authors briefly review cardiovascular side effects of non-steroidal anti-inflammatory drugs, the processes which potentially influence them, therapeutic consequences and their interaction with acetylsalicylic acid.


Assuntos
Anti-Inflamatórios não Esteroides/efeitos adversos , Sistema Cardiovascular/efeitos dos fármacos , Diclofenaco/efeitos adversos , Anti-Inflamatórios não Esteroides/administração & dosagem , Aspirina/administração & dosagem , Aspirina/efeitos adversos , Doenças Cardiovasculares/induzido quimicamente , Diclofenaco/administração & dosagem , Interações Medicamentosas , Humanos , Ibuprofeno/administração & dosagem , Ibuprofeno/efeitos adversos , Naproxeno/administração & dosagem , Naproxeno/efeitos adversos
8.
Hippocampus ; 24(12): 1506-23, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25044969

RESUMO

A subpopulation of GABAergic cells in cortical structures expresses CB1 cannabinoid receptors (CB1 ) on their axon terminals. To understand the function of these interneurons in information processing, it is necessary to uncover how they are embedded into neuronal circuits. Therefore, the proportion of GABAergic terminals expressing CB1 and the morphological and electrophysiological properties of CB1 -immunoreactive interneurons should be revealed. We investigated the ratio and the origin of CB1 -expressing inhibitory boutons in the CA3 region of the hippocampus. Using immunocytochemical techniques, we estimated that ∼40% of GABAergic axon terminals in different layers of CA3 also expressed CB1 . To identify the inhibitory cell types expressing CB1 in this region, we recorded and intracellularly labeled interneurons in hippocampal slices. CB1 -expressing interneurons showed distinct axonal arborization, and were classified as basket cells, mossy-fiber-associated cells, dendritic-layer-innervating cells or perforant-path-associated cells. In each morphological category, a substantial variability in axonal projection was observed. In contrast to the diverse morphology, the active and passive membrane properties were found to be rather similar. Using paired recordings, we found that pyramidal cells displayed large and fast unitary postsynaptic currents in response to activating basket and mossy-fiber-associated cells, while they showed slower and smaller synaptic events in pairs originating from interneurons that innervate the dendritic layer, which may be due to dendritic filtering. In addition, CB1 activation significantly reduced the amplitude of the postsynaptic currents in each cell pair tested. Our data suggest that CB1 -expressing interneurons with different axonal projections have comparable physiological characteristics, contributing to a similar proportion of GABAergic inputs along the somato-dendritic axis of CA3 pyramidal cells.


Assuntos
Região CA3 Hipocampal/fisiologia , Neurônios GABAérgicos/fisiologia , Interneurônios/fisiologia , Receptor CB1 de Canabinoide/metabolismo , Animais , Axônios/fisiologia , Região CA3 Hipocampal/citologia , Feminino , Neurônios GABAérgicos/citologia , Interneurônios/citologia , Masculino , Potenciais da Membrana/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Inibição Neural/fisiologia , Plasticidade Neuronal/fisiologia , Técnicas de Patch-Clamp , Terminações Pré-Sinápticas/fisiologia , Células Piramidais/fisiologia , Transmissão Sináptica/fisiologia , Técnicas de Cultura de Tecidos
9.
Psychiatry Res ; 328: 115459, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37696101

RESUMO

Assessing addictive behaviours comprehensively and efficiently is a challenge in both research and clinical practice. Consequently, we tested the psychometric properties of the Generalized Screener for Substance and Behavioural Addictions (SSBA-G), a novel, brief screening tool measuring functional impairment resulting from both substance and behavioural addictions. The SSBA-G was developed from the Screener for Substance and Behavioural Addictions (Schluter et al., 2018) and tested in four samples including university students in Canada (n = 481) and the US (n = 164) as well as community adults in Canada (n = 301), and Hungary (n = 79). Confirmatory factor analysis supported the hypothesized bifactor model of the SSBA-G. Receiver-operation characteristic analyses revealed high differentiation accuracy (AUC=0.86-.95), as well as identical ideal cut points across the Substance Addiction (SSBA-G-S) and Behavioural Addiction (SSBA-G-B) Subscales. Results indicated good-to-excellent sensitivity and moderate-to-good specificity. The SSBA-G demonstrated excellent internal consistency and test-retest reliability as well as promising concurrent validity in relation to the original SSBA and additional questions regarding addiction-related impairment. The SSBA-G also showed good convergent and divergent validity with indicators of general mental health. These results indicate that the SSBA-G is a psychometrically sound and efficient measure of addiction-related impairment across substances and excessive behaviours.


Assuntos
Comportamento Aditivo , Transtornos Relacionados ao Uso de Substâncias , Adulto , Humanos , Psicometria , Reprodutibilidade dos Testes , Transtornos Relacionados ao Uso de Substâncias/diagnóstico , Comportamento Aditivo/diagnóstico , Saúde Mental
10.
Phytother Res ; 26(3): 354-62, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21717515

RESUMO

Traditionally, Echinacea preparations are used as antiinflammatory agents and immune-enhancers. In addition to these effects, their anxiolytic potency has been recognized recently in laboratory tests. Our aim in this study was to uncover the potential effects of an Echinacea preparation on neuronal operations in the hippocampus, a brain region that is involved in anxiety and anxiety-related behaviors. Using in vitro electrophysiological techniques, we observed that excitatory synaptic transmission in hippocampal slices was significantly suppressed by an Echinacea extract found to be effective in anxiety tests. In contrast, no change in inhibitory synaptic transmission could be detected upon application of this extract. In addition, our experiments revealed that at low concentration the Echinacea extract reduced the spiking activity of CA1 pyramidal cells, while at high concentration increased it. This latter observation was parallel to the reduction in the magnitude of the h-current-mediated voltage responses in pyramidal cells. At any concentrations, the passive membrane properties of CA1 pyramidal cells were found to be unaltered by the Echinacea extract. In summary, the Echinacea extract can significantly regulate excitatory, but not inhibitory, synaptic transmission in the hippocampus, and this action might be involved in its anxiolytic effects observed in behaviour tests.


Assuntos
Echinacea/química , Hipocampo/efeitos dos fármacos , Fitoterapia , Preparações de Plantas/farmacologia , Células Piramidais/efeitos dos fármacos , Transmissão Sináptica/efeitos dos fármacos , Animais , Ansiolíticos/química , Ansiolíticos/farmacologia , Fenômenos Eletrofisiológicos , Hipocampo/fisiologia , Masculino , Neurônios/fisiologia , Técnicas de Patch-Clamp , Preparações de Plantas/administração & dosagem , Preparações de Plantas/química , Raízes de Plantas/química , Células Piramidais/fisiologia , Ratos , Ratos Wistar
11.
Orv Hetil ; 153(13): 514-7, 2012 Apr 01.
Artigo em Húngaro | MEDLINE | ID: mdl-22430007

RESUMO

UNLABELLED: The determination of carbohydrate deficient transferrin (CDT) concentration is primarily used in social security studies as a proof of regular alcohol consumption exceeding the amount of 60 grams per day. AIMS: The present study was performed to investigate into how carbohydrate deficient transferrin CDT values in serum are affected by the so-called food supplements and chemicals included in doping lists. METHODS: The investigation was carried out in 15 bodybuilders of two sport clubs and in 10 boxers. All sportsmen were males. In both groups serum carbohydrate deficient transferrin (CDT%), median red blood cell volume and (MCV) gamma-glutamyl-transpeptidase (GGT) values were measured. RESULTS: The authors found a significant difference between the two groups only in carbohydrate deficient transferrin CDT% that was the CDT% value in bodybuilders was twice as high as in boxers. CONCLUSION: Not all the details of the specificity of carbohydrate deficient transferrin (CDT) concentration are known, however, the remarkably high sensitivity of the method makes it suitable and probably economically effective as a pre-screening tool in doping tests.


Assuntos
Atletas , Dopagem Esportivo , Transferrina/análogos & derivados , Adulto , Biomarcadores/sangue , Boxe , Índices de Eritrócitos , Humanos , Masculino , Sensibilidade e Especificidade , Transferrina/metabolismo , Levantamento de Peso , gama-Glutamiltransferase/sangue
12.
Neuron ; 110(12): 1959-1977.e9, 2022 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-35489331

RESUMO

Ripples are brief high-frequency electrographic events with important roles in episodic memory. However, the in vivo circuit mechanisms coordinating ripple-related activity among local and distant neuronal ensembles are not well understood. Here, we define key characteristics of a long-distance projecting GABAergic cell group in the mouse hippocampus that selectively exhibits high-frequency firing during ripples while staying largely silent during theta-associated states when most other GABAergic cells are active. The high ripple-associated firing commenced before ripple onset and reached its maximum before ripple peak, with the signature theta-OFF, ripple-ON firing pattern being preserved across awake and sleep states. Controlled by septal GABAergic, cholinergic, and CA3 glutamatergic inputs, these ripple-selective cells innervate parvalbumin and cholecystokinin-expressing local interneurons while also targeting a variety of extra-hippocampal regions. These results demonstrate the existence of a hippocampal GABAergic circuit element that is uniquely positioned to coordinate ripple-related neuronal dynamics across neuronal assemblies.


Assuntos
Hipocampo , Interneurônios , Animais , Hipocampo/fisiologia , Interneurônios/fisiologia , Camundongos , Neurônios/fisiologia , Parvalbuminas , Vigília
13.
J Neurosci ; 30(45): 15134-45, 2010 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-21068319

RESUMO

Gamma frequency oscillations in cortical regions can be recorded during cognitive processes, including attention or memory tasks. These oscillations are generated locally as a result of reciprocal interactions between excitatory pyramidal cells and perisomatic inhibitory interneurons. Here, we examined the contribution of the three perisomatic interneuron types--the parvalbumin-containing fast-spiking basket cells (FSBCs) and axo-axonic cells (AACs), as well as the cholecystokinin-containing regular-spiking basket cells (RSBCs) to cholinergically induced oscillations in hippocampal slices, a rhythmic activity that captures several features of the gamma oscillations recorded in vivo. By analyzing the spiking activities of single neurons recorded in parallel with local field potentials, we found that all three cell types fired phase locked to the carbachol-induced oscillations, although with different frequencies and precision. During these oscillations, FSBCs fired the most with the highest accuracy compared with the discharge of AACs and RSBCs. In further experiments, we showed that activation of µ-opioid receptors by DAMGO ([D-Ala(2),N-Me-Phe(4),Gly(5)-ol]enkephalin acetate), which significantly reduced the inhibitory, but not excitatory, transmission, suppressed or even blocked network oscillations both in vitro and in vivo, leading to the desynchronization of pyramidal cell firing. Using paired recordings, we demonstrated that carbachol application blocked GABA release from RSBCs and reduced it from FSBCs and AACs, whereas DAMGO further suppressed the GABA release only from FSBCs, but not from AACs. These results collectively suggest that the rhythmic perisomatic inhibition, generating oscillatory fluctuation in local field potentials after carbachol treatment of hippocampal slices, is the result of periodic GABA release from FSBCs.


Assuntos
Relógios Biológicos/fisiologia , Hipocampo/fisiologia , Neurônios/fisiologia , Parvalbuminas/metabolismo , Receptores Colinérgicos/fisiologia , Análise de Variância , Animais , Anquirinas/metabolismo , Relógios Biológicos/efeitos dos fármacos , Carbacol/farmacologia , Colecistocinina/metabolismo , Eletrofisiologia , Feminino , Hipocampo/citologia , Hipocampo/efeitos dos fármacos , Imuno-Histoquímica , Potenciais Pós-Sinápticos Inibidores/efeitos dos fármacos , Potenciais Pós-Sinápticos Inibidores/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Microscopia Eletrônica , Potenciais Pós-Sinápticos em Miniatura/efeitos dos fármacos , Potenciais Pós-Sinápticos em Miniatura/fisiologia , Neurônios/citologia , Neurônios/efeitos dos fármacos
14.
Int J Cardiol ; 329: 153-161, 2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33359335

RESUMO

BACKGROUND: Although post-TAVI PAR is commonly seen, its exact evaluation, grading and the true impact on patients' survival are still debated. This single center study aimed to evaluate the effect of post transcatheter aortic valve implantation (TAVI) paravalvular aortic regurgitation (PAR) on patients' survival. The outcome was evaluated by the three most commonly used techniques just after TAVI in the interventional arena. METHODS: 201 high risk patients with severe symptomatic aortic stenosis underwent TAVI with the self-expandable system. The severity of post-TAVI PAR was prospectively evaluated by aortography and transesophageal echocardiography (TEE) using a four-class scheme and hemodynamic evaluation by calculation of the regurgitation index (RI). Median follow up time was 763 days. RESULTS: Post-TAVI PAR results of the three different modalities were concordant with each other (all p < 0.001). Patients with grade 0-I PAR by aortography had better long term outcomes compared to those who had grade II-III PAR (unadjusted HR 1.77 [95% CI, 1.04-3.01], p = 0.03). Although in multivariate analysis neither aortography nor TEE were shown to be significant predictors of survival, hemodynamic assessment using the exact RI result was a significant predictor of survival and its effect was found to be linear (adjusted HR 0.72 [95% CI, 0.52-0.98] for 10% point increase in RI, p = 0.03595). CONCLUSIONS: Among the three modalities that are frequently used to evaluate the outcome, post-TAVI RI showed the highest added predictive value for survival.


Assuntos
Insuficiência da Valva Aórtica , Estenose da Valva Aórtica , Substituição da Valva Aórtica Transcateter , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Insuficiência da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/cirurgia , Aortografia , Cateterismo Cardíaco , Ecocardiografia Transesofagiana , Hemodinâmica , Humanos , Prognóstico , Índice de Gravidade de Doença , Resultado do Tratamento
15.
Neuron ; 109(6): 997-1012.e9, 2021 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-33529646

RESUMO

Interneurons expressing cholecystokinin (CCK) and parvalbumin (PV) constitute two key GABAergic controllers of hippocampal pyramidal cell output. Although the temporally precise and millisecond-scale inhibitory regulation of neuronal ensembles delivered by PV interneurons is well established, the in vivo recruitment patterns of CCK-expressing basket cell (BC) populations has remained unknown. We show in the CA1 of the mouse hippocampus that the activity of CCK BCs inversely scales with both PV and pyramidal cell activity at the behaviorally relevant timescales of seconds. Intervention experiments indicated that the inverse coupling of CCK and PV GABAergic systems arises through a mechanism involving powerful inhibitory control of CCK BCs by PV cells. The tightly coupled complementarity of two key microcircuit regulatory modules demonstrates a novel form of brain-state-specific segregation of inhibition during spontaneous behavior.


Assuntos
Região CA1 Hipocampal/fisiologia , Interneurônios/fisiologia , Células Piramidais/fisiologia , Transmissão Sináptica/fisiologia , Animais , Colecistocinina/metabolismo , Feminino , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Parvalbuminas/metabolismo
16.
Neuron ; 109(23): 3838-3850.e8, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34648750

RESUMO

The axon initial segment of hippocampal pyramidal cells is a key subcellular compartment for action potential generation, under GABAergic control by the "chandelier" or axo-axonic cells (AACs). Although AACs are the only cellular source of GABA targeting the initial segment, their in vivo activity patterns and influence over pyramidal cell dynamics are not well understood. We achieved cell-type-specific genetic access to AACs in mice and show that AACs in the hippocampal area CA1 are synchronously activated by episodes of locomotion or whisking during rest. Bidirectional intervention experiments in head-restrained mice performing a random foraging task revealed that AACs inhibit CA1 pyramidal cells, indicating that the effect of GABA on the initial segments in the hippocampus is inhibitory in vivo. Finally, optogenetic inhibition of AACs at specific track locations induced remapping of pyramidal cell place fields. These results demonstrate brain-state-specific dynamics of a critical inhibitory controller of cortical circuits.


Assuntos
Interneurônios , Ácido gama-Aminobutírico , Animais , Axônios/fisiologia , Hipocampo/fisiologia , Interneurônios/fisiologia , Camundongos , Células Piramidais/fisiologia , Sinapses/fisiologia , Ácido gama-Aminobutírico/fisiologia
17.
Science ; 374(6574): 1492-1496, 2021 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-34914519

RESUMO

Locomotor speed is a basic input used to calculate one's position, but where this signal comes from is unclear. We identified neurons in the supramammillary nucleus (SuM) of the rodent hypothalamus that were highly correlated with future locomotor speed and reliably drove locomotion when activated. Robust locomotion control was specifically identified in Tac1 (substance P)­expressing (SuMTac1+) neurons, the activation of which selectively controlled the activity of speed-modulated hippocampal neurons. By contrast, Tac1-deficient (SuMTac1−) cells weakly regulated locomotion but potently controlled the spike timing of hippocampal neurons and were sufficient to entrain local network oscillations. These findings emphasize that the SuM not only regulates basic locomotor activity but also selectively shapes hippocampal neural activity in a manner that may support spatial navigation.


Assuntos
Hipocampo/fisiologia , Hipotálamo Posterior/fisiologia , Locomoção , Neurônios/fisiologia , Potenciais de Ação , Animais , Hipocampo/citologia , Hipotálamo Posterior/citologia , Camundongos , Camundongos Endogâmicos C57BL , Vias Neurais/fisiologia , Ratos , Navegação Espacial , Substância P/genética , Ritmo Teta
18.
Eur J Neurosci ; 31(12): 2234-46, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20529124

RESUMO

Perisomatic inhibition originates from three types of GABAergic interneurons in cortical structures, including parvalbumin-containing fast-spiking basket cells (FSBCs) and axo-axonic cells (AACs), as well as cholecystokinin-expressing regular-spiking basket cells (RSBCs). These interneurons may have significant impact in various cognitive processes, and are subjects of cholinergic modulation. However, it is largely unknown how cholinergic receptor activation modulates the function of perisomatic inhibitory cells. Therefore, we performed paired recordings from anatomically identified perisomatic interneurons and pyramidal cells in the CA3 region of the mouse hippocampus. We determined the basic properties of unitary inhibitory postsynaptic currents (uIPSCs) and found that they differed among cell types, e.g. GABA released from axon endings of AACs evoked uIPSCs with the largest amplitude and with the longest decay measured at room temperature. RSBCs could also release GABA asynchronously, the magnitude of the release increasing with the discharge frequency of the presynaptic interneuron. Cholinergic receptor activation by carbachol significantly decreased the uIPSC amplitude in all three types of cell pairs, but to different extents. M2-type muscarinic receptors were responsible for the reduction in uIPSC amplitudes in FSBC- and AAC-pyramidal cell pairs, while an antagonist of CB(1) cannabinoid receptors recovered the suppression in RSBC-pyramidal cell pairs. In addition, carbachol suppressed or even eliminated the short-term depression of uIPSCs in FSBC- and AAC-pyramidal cell pairs in a frequency-dependent manner. These findings suggest that not only are the basic synaptic properties of perisomatic inhibitory cells distinct, but acetylcholine can differentially control the impact of perisomatic inhibition from different sources.


Assuntos
Região CA3 Hipocampal/metabolismo , Interneurônios/metabolismo , Células Piramidais/metabolismo , Receptores Colinérgicos/metabolismo , Sinapses/metabolismo , Animais , Região CA3 Hipocampal/citologia , Carbacol/farmacologia , Agonistas Colinérgicos/farmacologia , Potenciais Pós-Sinápticos Inibidores/efeitos dos fármacos , Potenciais Pós-Sinápticos Inibidores/fisiologia , Interneurônios/citologia , Potenciais da Membrana/fisiologia , Camundongos , Camundongos Transgênicos , Técnicas de Patch-Clamp , Células Piramidais/citologia , Transmissão Sináptica/fisiologia , Ácido gama-Aminobutírico/metabolismo
19.
Eur J Anaesthesiol ; 27(2): 153-61, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19809324

RESUMO

BACKGROUND AND OBJECTIVE: In spite of the widespread clinical use of articaine and ropivacaine there is little information available on the effects of these drugs on myocardial Ca handling. In the present study, therefore, the concentration-dependent effects of articaine and ropivacaine on the components of intracellular Ca handling were studied and compared in canine ventricular myocardium. METHODS: Contractility was measured in ventricular trabeculae, [Ca]i transients were recorded from electrically stimulated isolated ventricular myocytes loaded with the calcium-sensitive dye fura-2, L-type Ca current was recorded under whole cell patch clamp conditions, and the release and reuptake of Ca was monitored in sarcoplasmic reticulum vesicles. RESULTS: Articaine and ropivacaine caused a reversible and concentration-dependent decrease in amplitude of the [Ca]i transient (EC50 = 87.4 +/- 12 and 99.3 +/- 17 micromol l, respectively), which was congruent with the reduction obtained for contractility (EC50 = 73.7 +/- 10 and 72.8 +/- 14 micromol l, respectively). No significant change in diastolic [Ca]i was found. L-type Ca current was significantly reduced by articaine and ropivacaine with EC50 values of 327 +/- 56 and 263 +/- 67 micromol l, respectively. Neither Ca release and Ca uptake nor the ATPase activity of the sarcoplasmic reticulum vesicles was altered by articaine or ropivacaine at concentrations less than 200 micromol l. In summary, articaine and ropivacaine caused no significant changes at the therapeutically relevant concentrations of the micromolar range. No significant differences between the effects of articaine and ropivacaine on contractility, [Ca]i transients, L-type Ca current, and sarcoplasmic reticulum Ca release and uptake were observed. CONCLUSIONS: Under conditions of normal application both articaine and ropivacaine are free of cardiodepressant effects; however, a negative inotropic action can be anticipated in cases of accidental intravenous injection or overdose. The observed negative inotropic actions of articaine and ropivacaine are similar in magnitude, and can be mainly attributed to a reduction in net trans-sarcolemmal Ca influx.


Assuntos
Amidas/farmacologia , Anestésicos Locais/farmacologia , Cálcio/metabolismo , Carticaína/farmacologia , Amidas/administração & dosagem , Anestésicos Locais/administração & dosagem , Animais , Canais de Cálcio Tipo L/efeitos dos fármacos , Canais de Cálcio Tipo L/metabolismo , Carticaína/administração & dosagem , Cães , Relação Dose-Resposta a Droga , Feminino , Ventrículos do Coração/metabolismo , Masculino , Contração Miocárdica/efeitos dos fármacos , Miocárdio/metabolismo , Técnicas de Patch-Clamp , Ropivacaina , Retículo Sarcoplasmático/efeitos dos fármacos , Retículo Sarcoplasmático/metabolismo
20.
Radiat Res ; 193(5): 407-424, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32134362

RESUMO

Radiotherapy, surgery and the chemotherapeutic agent temozolomide (TMZ) are frontline treatments for glioblastoma multiforme (GBM). However beneficial, GBM treatments nevertheless cause anxiety or depression in nearly 50% of patients. To further understand the basis of these neurological complications, we investigated the effects of combined radiotherapy and TMZ chemotherapy (combined treatment) on neurological impairments using a mouse model. Five weeks after combined treatment, mice displayed anxiety-like behaviors, and at 15 weeks both anxiety- and depression-like behaviors were observed. Relevant to the known roles of the serotonin axis in mood disorders, we found that 5HT1A serotonin receptor levels were decreased by ∼50% in the hippocampus at both early and late time points, and a 37% decrease in serotonin levels was observed at 15 weeks postirradiation. Furthermore, chronic treatment with the selective serotonin reuptake inhibitor fluoxetine was sufficient for reversing combined treatment-induced depression-like behaviors. Combined treatment also elicited a transient early increase in activated microglia in the hippocampus, suggesting therapy-induced neuroinflammation that subsided by 15 weeks. Together, the results of this study suggest that interventions targeting the serotonin axis may help ameliorate certain neurological side effects associated with the clinical management of GBM to improve the overall quality of life for cancer patients.


Assuntos
Neurologia , Radioterapia/efeitos adversos , Temozolomida/efeitos adversos , Animais , Ansiedade/diagnóstico , Ansiedade/etiologia , Ansiedade/metabolismo , Comportamento Animal/efeitos dos fármacos , Comportamento Animal/efeitos da radiação , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/radioterapia , Região CA1 Hipocampal/efeitos dos fármacos , Região CA1 Hipocampal/patologia , Região CA1 Hipocampal/efeitos da radiação , Terapia Combinada/efeitos adversos , Depressão/induzido quimicamente , Depressão/etiologia , Glioblastoma/tratamento farmacológico , Glioblastoma/radioterapia , Masculino , Camundongos , Neurônios/efeitos dos fármacos , Neurônios/patologia , Neurônios/efeitos da radiação , Receptor 5-HT1A de Serotonina/metabolismo , Serotonina/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/efeitos da radiação , Temozolomida/uso terapêutico
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