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1.
Phys Rev Lett ; 130(12): 122502, 2023 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-37027859

RESUMEN

The excited states of N=44 ^{74}Zn were investigated via γ-ray spectroscopy following ^{74}Cu ß decay. By exploiting γ-γ angular correlation analysis, the 2_{2}^{+}, 3_{1}^{+}, 0_{2}^{+}, and 2_{3}^{+} states in ^{74}Zn were firmly established. The γ-ray branching and E2/M1 mixing ratios for transitions deexciting the 2_{2}^{+}, 3_{1}^{+}, and 2_{3}^{+} states were measured, allowing for the extraction of relative B(E2) values. In particular, the 2_{3}^{+}→0_{2}^{+} and 2_{3}^{+}→4_{1}^{+} transitions were observed for the first time. The results show excellent agreement with new microscopic large-scale shell-model calculations, and are discussed in terms of underlying shapes, as well as the role of neutron excitations across the N=40 gap. Enhanced axial shape asymmetry (triaxiality) is suggested to characterize ^{74}Zn in its ground state. Furthermore, an excited K=0 band with a significantly larger softness in its shape is identified. A shore of the N=40 "island of inversion" appears to manifest above Z=26, previously thought as its northern limit in the chart of the nuclides.

2.
Phys Rev Lett ; 129(11): 112501, 2022 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-36154392

RESUMEN

The reduced transition probabilities for the 4_{1}^{+}→2_{1}^{+} and 2_{1}^{+}→0_{1}^{+} transitions in ^{92}Mo and ^{94}Ru and for the 4_{1}^{+}→2_{1}^{+} and 6_{1}^{+}→4_{1}^{+} transitions in ^{90}Zr have been determined in this experiment making use of a multinucleon transfer reaction. These results have been interpreted on the basis of realistic shell-model calculations in the f_{5/2}, p_{3/2}, p_{1/2}, and g_{9/2} proton valence space. Only the combination of extensive lifetime information and large scale shell-model calculations allowed the extent of the seniority conservation in the N=50 g_{9/2} orbital to be understood. The conclusion is that seniority is largely conserved in the first πg_{9/2} orbital.

3.
Phys Rev Lett ; 126(7): 072501, 2021 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-33666458

RESUMEN

We studied the proton-rich T_{z}=-1 nucleus ^{70}Kr through inelastic scattering at intermediate energies in order to extract the reduced transition probability, B(E2;0^{+}→2^{+}). Comparison with the other members of the A=70 isospin triplet, ^{70}Br and ^{70}Se, studied in the same experiment, shows a 3σ deviation from the expected linearity of the electromagnetic matrix elements as a function of T_{z}. At present, no established nuclear structure theory can describe this observed deviation quantitatively. This is the first violation of isospin symmetry at this level observed in the transition matrix elements. A heuristic approach may explain the anomaly by a shape change between the mirror nuclei ^{70}Kr and ^{70}Se contrary to the model predictions.

4.
Phys Rev Lett ; 124(4): 042503, 2020 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-32058764

RESUMEN

There is sparse direct experimental evidence that atomic nuclei can exhibit stable "pear" shapes arising from strong octupole correlations. In order to investigate the nature of octupole collectivity in radium isotopes, electric octupole (E3) matrix elements have been determined for transitions in ^{222,228}Ra nuclei using the method of sub-barrier, multistep Coulomb excitation. Beams of the radioactive radium isotopes were provided by the HIE-ISOLDE facility at CERN. The observed pattern of E3 matrix elements for different nuclear transitions is explained by describing ^{222}Ra as pear shaped with stable octupole deformation, while ^{228}Ra behaves like an octupole vibrator.

5.
Phys Rev Lett ; 120(2): 022502, 2018 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-29376727

RESUMEN

The g factor of the 56 ns half-life isomeric state in ^{128}Cs has been measured using the time-differential perturbed angular distribution method. This state is the bandhead of the positive-parity chiral rotational band, which emerges when an unpaired proton, an unpaired neutron hole, and an even-even core are coupled such that their angular momentum vectors are aplanar (chiral configuration). g-factor measurements can give important information on the relative orientation of the three angular momentum vectors. The measured g factor g=+0.59(1) shows that there is an important contribution of the core rotation in the total angular momentum of the isomeric state. Moreover, a quantitative theoretical analysis supports the conclusion that the three angular momentum vectors lie almost in one plane, which suggests that the chiral configuration in ^{128}Cs demonstrated in previous works by characteristic patterns of electromagnetic transitions appears only above some value of the total nuclear spin.

6.
Phys Rev Lett ; 121(19): 192502, 2018 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-30468583

RESUMEN

Lifetime measurements of excited states of the light N=52 isotones ^{88}Kr, ^{86}Se, and ^{84}Ge have been performed, using the recoil distance Doppler shift method and VAMOS and AGATA spectrometers for particle identification and gamma spectroscopy, respectively. The reduced electric quadrupole transition probabilities B(E2;2^{+}→0^{+}) and B(E2;4^{+}→2^{+}) were obtained for the first time for the hard-to-reach ^{84}Ge. While the B(E2;2^{+}→0^{+}) values of ^{88}Kr, ^{86}Se saturate the maximum quadrupole collectivity offered by the natural valence (3s, 2d, 1g_{7/2}, 1h_{11/2}) space of an inert ^{78}Ni core, the value obtained for ^{84}Ge largely exceeds it, suggesting that shape coexistence phenomena, previously reported at N≲49, extend beyond N=50. The onset of collectivity at Z=32 is understood as due to a pseudo-SU(3) organization of the proton single-particle sequence reflecting a clear manifestation of pseudospin symmetry. It is realized that the latter provides actually reliable guidance for understanding the observed proton and neutron single particle structure in the whole medium-mass region, from Ni to Sn, pointing towards the important role of the isovector-vector ρ field in shell-structure evolution.

7.
Colorectal Dis ; 20(4): 321-330, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-28963746

RESUMEN

AIM: The aim of this study was to assess the expression of vascular endothelial growth factor (VEGF) as a key proangiogenic factor and determine whether there is any correlation between its expression and clinical symptoms or endoscopic changes in patients with chronic radiation proctitis (ChRP). METHOD: Fifty patients who had all undergone radiotherapy for prostate, cervical or uterine cancer were included in the study (37 women, 13 men). There was a control group of 20 patients (9 women, 11 men). The Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer (RTOG/EORTC) scoring system was used for grading the severity of the proctitis. Endoscopic scoring of late rectal mucosal damage was performed using Gilinsky's classification. Serum levels of VEGF were analysed by the enzyme-linked immunosorbent assay method. RESULTS: Most patients presented with Grade 1 symptoms. Endoscopic assessment showed that most patients had Grade 1 late rectal mucosal damage. The predominant endoscopic finding was the presence of telangiectasia. Assessment of VEGF correlation between the control group and the degrees of endoscopic changes showed statistically significant differences for all three degrees (P < 0.0001, P = 0.0251 and P = 0.0005, respectively). Due to the small numbers of patients with Grades 2 and 3 symptoms using the RTOG/EORTC scoring system, they were grouped with Grades 1 and 4 respectively forming two groups for statistical purposes. VEGF expression differed significantly between controls and group I and between controls and group II (P = 0.0001, P = 0.0009, respectively). CONCLUSION: A significant increase in VEGF expression was found to correlate with clinical symptoms and endoscopic rectal mucosa changes in patients with ChRP, suggesting that it may play an important role in pathological angiogenesis.


Asunto(s)
Mucosa Intestinal/efectos de la radiación , Proctitis/sangre , Traumatismos por Radiación/sangre , Recto/efectos de la radiación , Factor A de Crecimiento Endotelial Vascular/sangre , Adulto , Anciano , Anciano de 80 o más Años , Endoscopía del Sistema Digestivo , Femenino , Humanos , Mucosa Intestinal/irrigación sanguínea , Masculino , Persona de Mediana Edad , Proctitis/etiología , Proctitis/patología , Neoplasias de la Próstata/radioterapia , Traumatismos por Radiación/patología , Recto/irrigación sanguínea , Índice de Severidad de la Enfermedad , Telangiectasia/etiología , Neoplasias del Cuello Uterino/radioterapia , Neoplasias Uterinas/radioterapia
8.
Phys Rev Lett ; 118(22): 222501, 2017 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-28621970

RESUMEN

Fast-neutron-induced fission of ^{238}U at an energy just above the fission threshold is studied with a novel technique which involves the coupling of a high-efficiency γ-ray spectrometer (MINIBALL) to an inverse-kinematics neutron source (LICORNE) to extract charge yields of fission fragments via γ-γ coincidence spectroscopy. Experimental data and fission models are compared and found to be in reasonable agreement for many nuclei; however, significant discrepancies of up to 600% are observed, particularly for isotopes of Sn and Mo. This indicates that these models significantly overestimate the standard 1 fission mode and suggests that spherical shell effects in the nascent fission fragments are less important for low-energy fast-neutron-induced fission than for thermal neutron-induced fission. This has consequences for understanding and modeling the fission process, for experimental nuclear structure studies of the most neutron-rich nuclei, for future energy applications (e.g., Generation IV reactors which use fast-neutron spectra), and for the reactor antineutrino anomaly.

9.
Mol Biol Rep ; 44(6): 455-461, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28993955

RESUMEN

Gastrointestinal tract conditions are frequently associated with low bone mineral density and increased risk of fractures due to osteoporosis, the latter concerning particularly inflammatory bowel disease (IBD) patients. One of the candidate genes involved in osteoporosis is the transforming growth factor beta-1 (TGFB1) whose polymorphisms may be responsible for the development of this disease. The aim of this study was to analyse the frequency of TGFB1 polymorphic variants and determine the association between the c.29T>C TGFB1 polymorphism, and bone mineral density and fractures in IBD patients. The study subjects included 198 IBD patients [100 suffering from Crohn's disease (CD) and 98 from ulcerative colitis (UC)] and 41 healthy volunteers as a control group. Densitometric bone measurements were obtained using dual energy X-ray absorptiometry. The TGFB1 genotyping was conducted using restriction fragments length polymorphism. We conducted an analysis of genotype distribution's concordance with Hardy-Weinberg equilibrium. We found statistically significant differences in lumbar spine (L2-L4) and femoral neck BMD and T-scores between CD, UC and control subgroups. The distribution of TGFB1 polymorphic variants among CD and UC patients was concordant with Hardy-Weinberg equilibrium. There were no statistically significant differences in densitometric parameters (lumbar spine and femoral neck BMD, T-score, and Z-score) between carriers of different TGFB1 polymorphisms among IBD (CD and UC) patients nor among controls. We have found no statistically significant differences in the prevalence of low-energy fractures between groups of different TGFB1 polymorphic variant carriers. The allele dose effect, recessive effect and dominant effect analysis did not show an association between low-energy fractures and the TGFB1 polymorphisms among CD and UC patients. We have not observed an association between the c.29T>C TGFB1 polymorphic variant and the bone mineral density within the cancellous and cortical bones (L2-L4 and femoral neck, respectively), or the occurrence of fractures among the IBD patients and their family members.


Asunto(s)
Enfermedades Inflamatorias del Intestino/genética , Factor de Crecimiento Transformador beta1/genética , Adulto , Alelos , Densidad Ósea/genética , Colitis Ulcerosa/genética , Enfermedad de Crohn/genética , Estudios Transversales , Femenino , Fracturas Óseas/genética , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Osteoporosis/genética , Osteoporosis/metabolismo , Polimorfismo de Nucleótido Simple , Factores de Riesgo , Factor de Crecimiento Transformador beta1/metabolismo
10.
J Pharmacol Exp Ther ; 356(1): 157-69, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26462538

RESUMEN

The α7 pentamer nicotinic acetylcholine receptors (nAChRs) are a target in transduction of anti-inflammatory signals from the central nervous system to the gastrointestinal (GI) tract. The aim of this study was to investigate the anti-inflammatory action of the novel α7 nAChR partial agonist encenicline and to determine the mechanism underlying its activity. Anti-inflammatory activity of encenicline was evaluated using trinitrobenzenesulfonic acid (TNBS)- and dextran sulfate sodium (DSS)-induced models of colitis. Macroscopic score, ulcer score, colon length and thickness, as well as myeloperoxidase (MPO) activity were recorded. Immunohistochemistry (IHC) was used to measure the infiltration of immune cells in the colon. Furthermore, we employed flow cytometry to determine the effect of encenicline on frequencies of FoxP3(+) and interleukin (IL)-17A(+) T cells in the mouse colon. Encenicline attenuated TNBS- and DSS-induced colitis in mice via α7 nAChRs, as indicated by significantly reduced macroscopic parameters and MPO activity. Treatment with encenicline significantly reduced the infiltration of macrophages, neutrophils, and B cells in the colon of TNBS-treated animals, as indicated by IHC. In the TNBS model encenicline reduced the frequency of FoxP3(+) IL-17A(+) T cells in the colon. In the DSS-model treatment encenicline increased the frequency of FoxP3(+) T cells and reduced IL-17A(+) T cells. Stimulation of α7 nAChR with partial agonist encenicline alleviates colitis via alteration of the number and/or activation status of the immune cells in the gut, emphasizing a potential role of α7 nAChRs as a target for anticolitic drugs.


Asunto(s)
Colitis Ulcerosa/tratamiento farmacológico , Colitis Ulcerosa/patología , Colon/patología , Agonistas Nicotínicos/uso terapéutico , Quinuclidinas/uso terapéutico , Tiofenos/uso terapéutico , Receptor Nicotínico de Acetilcolina alfa 7/agonistas , Animales , Colitis Ulcerosa/inducido químicamente , Sulfato de Dextran , Citometría de Flujo , Factores de Transcripción Forkhead/metabolismo , Hexametonio/farmacología , Interleucina-17/metabolismo , Masculino , Ratones , Ratones Endogámicos BALB C , Antagonistas Nicotínicos/farmacología , Peroxidasa/metabolismo , Linfocitos T/efectos de los fármacos , Linfocitos T/metabolismo , Ácido Trinitrobencenosulfónico
11.
Phys Rev Lett ; 116(2): 022701, 2016 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-26824536

RESUMEN

Neutron-rich {96,98}Sr isotopes have been investigated by safe Coulomb excitation of radioactive beams at the REX-ISOLDE facility. Reduced transition probabilities and spectroscopic quadrupole moments have been extracted from the differential Coulomb excitation cross sections. These results allow, for the first time, the drawing of definite conclusions about the shape coexistence of highly deformed prolate and spherical configurations. In particular, a very small mixing between the coexisting states is observed, contrary to other mass regions where strong mixing is present. Experimental results have been compared to beyond-mean-field calculations using the Gogny D1S interaction in a five-dimensional collective Hamiltonian formalism, which reproduce the shape change at N=60.

13.
Phys Rev Lett ; 117(6): 062501, 2016 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-27541463

RESUMEN

Shape parameters of a weakly deformed ground-state band and highly deformed slightly triaxial sideband in ^{42}Ca were determined from E2 matrix elements measured in the first low-energy Coulomb excitation experiment performed with AGATA. The picture of two coexisting structures is well reproduced by new state-of-the-art large-scale shell model and beyond-mean-field calculations. Experimental evidence for superdeformation of the band built on 0_{2}^{+} has been obtained and the role of triaxiality in the A∼40 mass region is discussed. Furthermore, the potential of Coulomb excitation as a tool to study superdeformation has been demonstrated for the first time.

14.
Phys Rev Lett ; 115(17): 172501, 2015 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-26551106

RESUMEN

Excited states of the neutron-rich nuclei (97,99)Rb were populated for the first time using the multistep Coulomb excitation of radioactive beams. Comparisons of the results with particle-rotor model calculations provide clear identification for the ground-state rotational band of (97)Rb as being built on the πg(9/2) [431] 3/2(+) Nilsson-model configuration. The ground-state excitation spectra of the Rb isotopes show a marked distinction between single-particle-like structures below N=60 and rotational bands above. The present study defines the limits of the deformed region around A∼100 and indicates that the deformation of (97)Rb is essentially the same as that observed well inside the deformed region. It further highlights the power of the Coulomb-excitation technique for obtaining spectroscopic information far from stability. The (99)Rb case demonstrates the challenges of studies with very short-lived postaccelerated radioactive beams.

15.
Genet Mol Res ; 14(1): 2850-9, 2015 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-25867434

RESUMEN

Glutathione S-transferases (GST) A1 and P1 are crucial enzymes involved in the biotransformation of drugs, carcinogens, and toxins, and their activity may influence drug response, susceptibility to diseases, and carcinogenesis. The genes encoding these enzymes, GSTA1 and GSTP1, have been examined in many studies because of their genetic variability, which may affect enzymatic activity. The goal of this study was to determine the distribution of the alleles GSTA1*A/*B and GSTP1*A, *B, and *C in the Polish population. A total of 160 subjects from the Polish population were genotyped for 2 polymorphisms (I105V and A114V) in the GSTP1 gene using pyrosequencing. The promoter region of the GSTA1 gene was screened using sequencing. The detected variants were subjected to haplotype analysis. We found that the distribution of the alleles GSTA1*A/*B and GSTP1*A, *B, and *C in the Polish population correspond to the results of studies in Caucasians. Furthermore, we identified additional single nucleotide polymorphisms, excluding 3 well-known changes (G-52A, C-69T, T-567G), which are linked to alleles GSTA1*A/*B, that affect enzyme activity. A total of 4 haplotypes were identified in 160 Polish individuals.


Asunto(s)
Gutatión-S-Transferasa pi/genética , Glutatión Transferasa/genética , Polimorfismo de Nucleótido Simple , Regiones Promotoras Genéticas/genética , Alelos , Frecuencia de los Genes , Genotipo , Haplotipos , Humanos , Desequilibrio de Ligamiento , Polonia , Análisis de Secuencia de ADN , Población Blanca/genética
16.
Sci Rep ; 13(1): 6926, 2023 04 28.
Artículo en Inglés | MEDLINE | ID: mdl-37117325

RESUMEN

Environmental pollution by heavy metals affects both urban and non-urban areas of Europe and the world. The use of bioindicator plants for the detection of these pollutants is a common practice. An important property of potential bioindicators is their easy availability and wide distribution range, which means that they can be practically used over a wide area. Therefore, common and widely distributed weeds: Trifolium pratense L., Rumex acetosa L., Amaranthus retroflexus L., Plantago lanceolata L., ornamental species Alcea rosea L., and Lolium multiflorum L. var. Ponto were selected as a potential bioindicators of heavy metals (Cd, Pb, Cu, Zn). Plants were exposed in the same soil conditions in three sample sites in the Poznan city. It was found that all species had heavy metal accumulation potential, especially A. rosea, P. lanceolata and L. multiflorum for Zn (BCF = 6.62; 5.17; 4.70) and A. rosea, P. lanceolata for Cd (BCF = 8.51; 6.94). Translocation of Cu and Zn was the most effective in T. pratense (TFCu = 2.55; TFZn = 2.67) and in A. retroflexus (TFCu = 1.50; TFZn = 2.23). Cd translocation was the most efficient in T. pratense (TFCd = 1.97), but PB was the most effective translocated in A. retroflexus (TFPb = 3.09).. Based on physiological response to stress, it was detected an increasing level of hydrogen peroxide (H2O2) in roots and leaves of all samples, with the highest in all organs of A. rosea. Enzymatic activity levels of CAT, APOX, and also the marker of polyunsaturated fatty acid peroxidation MDA, were higher after 6 weeks of exposure in comparison to control samples and varied in time of exposure and between species and exposure. After the experiment, in almost all samples we detected a reduction of chlorophyll content and relative water content, but in efficiency of photosynthesis parameters: net photosynthesis rate, intercellular CO2 concentration and stomatal conductance, we noted increased values, which proved the relatively good condition of the plants. The examined weeds are good bioindicators of heavy metal contamination, and their combined use makes it possible to comprehensively detection of environmental threats.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Biomarcadores Ambientales , Cadmio , Monitoreo Biológico , Peróxido de Hidrógeno , Plomo , Metales Pesados/análisis , Suelo , Malezas , Contaminantes del Suelo/análisis , Monitoreo del Ambiente
17.
J Obstet Gynaecol ; 32(1): 81-6, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22185545

RESUMEN

The aim of this study was to investigate the clinical features and prognosis in patients with gynaecological epithelial cancers metastasised to bones. A total of 26 patients were studied retrospectively. Clinical and pathological data were analysed along with a follow-up. It was found that the interval from primary diagnosis of cancer until bony relapse varied between 0 and 163 months (31.4 ± 36.8). Bone metastases were solitary in 11 cases and multifocal in 15 cases. A total of 14 patients demonstrated only bony metastases while 12 had both bony and non-bony metastases. The time to follow-up from the diagnosis of osseous relapse varied between 1 and 43 months (10.0 ± 10.4). During follow-ups, 13 patients died and 13 patients survived. In both univariate and multivariate analyses, synchronous non-bony metastases and symptomatic treatment without oncological therapy impaired prognosis. It was concluded that even in the presence of multiple bone metastases, some patients may benefit from radiotherapy, chemotherapy or a combination of both, rather than palliative care alone, providing they do not have additional soft tissue metastases.


Asunto(s)
Adenocarcinoma/secundario , Neoplasias Óseas/secundario , Carcinoma de Células Escamosas/secundario , Neoplasias de los Genitales Femeninos/patología , Adenocarcinoma/mortalidad , Adulto , Anciano , Neoplasias Óseas/mortalidad , Carcinoma de Células Escamosas/mortalidad , Femenino , Neoplasias de los Genitales Femeninos/mortalidad , Humanos , Persona de Mediana Edad , Polonia/epidemiología , Estudios Retrospectivos
18.
J Obstet Gynaecol ; 32(6): 585-9, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22779968

RESUMEN

The aim of the study was to assess the clinical features and prognosis in patients with epithelial ovarian cancer (EOC) metastasised to the central nervous system (CNS). A total of 15 patients were studied retrospectively. Clinical and pathological data and follow-up were analysed. It was found that at the diagnosis of primary EOC, the patients were 41-69 years old (56.6 ± 8.3). The interval from diagnosis of primary EOC until the relapse was 2-39 months (19.1 ± 10.5). Palliative radiotherapy was the treatment of the CNS relapse in 13 patients (86.7%). The follow-up after CNS relapse varied 0.5-15 months (4.7 ± 4.2). At the time of retrospective analysis, none of the patients were still alive. Multifocality of the CNS metastases, the presence of synchronous extracranial metastases and locations in the brain were not associated with survival. It was concluded that the development of the CNS metastases seems to be not uncommon in patients with advanced ovarian cancer. Despite oncological treatment, they are indicators of poor prognosis, and most of the patients do not survive beyond the first year of follow-up.


Asunto(s)
Adenocarcinoma/secundario , Neoplasias Encefálicas/secundario , Encéfalo/patología , Neoplasias Ováricas/patología , Adenocarcinoma/mortalidad , Adulto , Anciano , Neoplasias Encefálicas/mortalidad , Femenino , Humanos , Persona de Mediana Edad , Neoplasias Ováricas/mortalidad , Polonia/epidemiología , Pronóstico
20.
Neuroscience ; 446: 124-136, 2020 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-32858142

RESUMEN

Glutamine is an astroglia-derived precursor of the neurotransmitter glutamate, and its astroglia-to-neuron transfer is controlled by distinct glutamine transporters on the astrocytic and neuronal sites. In this study, we focused on the role of astrocytic glutamine efflux-mediating system N transporter SN1 in the maintenance of glutamatergic neurotransmission by analyzing the electrophysiological parameters ex vivo in the brain slices from control mice and mice in which vivo-morpholino technique was used to diminish SN1 protein. The glutamatergic transmission was characterized by electrophysiological recordings, ultrastructure of neuron terminals, and determination of proteins related to glutamate synaptic transmission: synaptophysin, synaptotagmin, and vit1A. The space-restricted ∼51,5% reduction of SN1 protein did not affect the expression of the neuronal glutamine transporter SAT2. SN1 depletion resulted in a reduction of field potentials (FPs), unaltered frequency of spontaneous and miniature excitatory postsynaptic currents (sEPSCs/mEPSCs), and presented a tendency towards a decrease of long-term potentiation (LTP). Ultrastructurally, preserved number of synaptic vesicles, primarily localized centrally of the cell body, correlates with unchanged levels of synaptic proteins. Collectively, the study indicates that glutamatergic transmission proceeds relatively independently of the SN1 - mediated glutamine transfer to the synapse.


Asunto(s)
Sistemas de Transporte de Aminoácidos Neutros , Sistemas de Transporte de Aminoácidos Neutros/metabolismo , Animales , Lóbulo Frontal/metabolismo , Ácido Glutámico , Glutamina , Ratones , Transmisión Sináptica
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