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1.
Braz J Med Biol Res ; 53(3): e8876, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32077463

RESUMO

The immune stimulatory and anti-neoplastic functions of type I interferon have long been applied for the treatment of melanoma. However, the systemic application of high levels of this recombinant protein is often met with toxicity. An approach that provides localized, yet transient, production of type I interferon may overcome this limitation. We propose that the use of mesenchymal stem cells (MSCs) as delivery vehicles for the production of interferon-ß (IFNß) may be beneficial when applied together with our cancer gene therapy approach. In our previous studies, we have shown that adenovirus-mediated gene therapy with IFNß was especially effective in combination with p19Arf gene transfer, resulting in immunogenic cell death. Here we showed that MSCs derived from mouse adipose tissue were susceptible to transduction with adenovirus, expressed the transgene reliably, and yet were not especially sensitive to IFNß production. MSCs used to produce IFNß inhibited B16 mouse melanoma cells in a co-culture assay. Moreover, the presence of p19Arf in the B16 cells sensitizes them to the IFNß produced by the MSCs. These data represent a critical demonstration of the use of MSCs as carriers of adenovirus encoding IFNß and applied as an anti-cancer strategy in combination with p19Arf gene therapy.


Assuntos
Inibidor p16 de Quinase Dependente de Ciclina/administração & dosagem , Interferon beta/metabolismo , Melanoma Experimental/terapia , Células-Tronco Mesenquimais/metabolismo , Animais , Linhagem Celular Tumoral , Proliferação de Células , Modelos Animais de Doenças , Terapia Genética , Masculino , Melanoma Experimental/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Transdução Genética
2.
Braz. j. med. biol. res ; 53(3): e8876, 2020. graf
Artigo em Inglês | LILACS | ID: biblio-1089338

RESUMO

The immune stimulatory and anti-neoplastic functions of type I interferon have long been applied for the treatment of melanoma. However, the systemic application of high levels of this recombinant protein is often met with toxicity. An approach that provides localized, yet transient, production of type I interferon may overcome this limitation. We propose that the use of mesenchymal stem cells (MSCs) as delivery vehicles for the production of interferon-β (IFNβ) may be beneficial when applied together with our cancer gene therapy approach. In our previous studies, we have shown that adenovirus-mediated gene therapy with IFNβ was especially effective in combination with p19Arf gene transfer, resulting in immunogenic cell death. Here we showed that MSCs derived from mouse adipose tissue were susceptible to transduction with adenovirus, expressed the transgene reliably, and yet were not especially sensitive to IFNβ production. MSCs used to produce IFNβ inhibited B16 mouse melanoma cells in a co-culture assay. Moreover, the presence of p19Arf in the B16 cells sensitizes them to the IFNβ produced by the MSCs. These data represent a critical demonstration of the use of MSCs as carriers of adenovirus encoding IFNβ and applied as an anti-cancer strategy in combination with p19Arf gene therapy.


Assuntos
Animais , Masculino , Coelhos , Melanoma Experimental/terapia , Interferon beta/metabolismo , Inibidor p16 de Quinase Dependente de Ciclina/administração & dosagem , Células-Tronco Mesenquimais/metabolismo , Transdução Genética , Melanoma Experimental/metabolismo , Terapia Genética , Linhagem Celular Tumoral , Proliferação de Células , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL
3.
Eur J Clin Nutr ; 71(12): 1449-1454, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28901336

RESUMO

BACKGROUND/OBJECTIVES: Vitamin D and probiotics are nutrients of interest in the context of type 1 diabetes (T1D). We assessed the prevalence of and factors associated with vitamin D and probiotic supplementations among young children with genetic risk of T1D. SUBJECTS/METHODS: Use of supplements during the first 2 years of life was collected prospectively from 8674 children in The Environmental Determinants of Diabetes in the Young (TEDDY) study. RESULTS: Single and/or multivitamin/mineral (MVM) supplements were reported by 81% of the children. The majority of participants in Finland, Germany and Sweden (97-99%) and 50% in the United States received vitamin D supplements that were mostly MVMs. Probiotics use varied from 6% in the United States to 60% in Finland and was primarily from probiotics-only preparations. More than 80% of the vitamin D and probiotics supplementation was initiated during infancy, and more than half of the uses lasted longer than a year. Being the first child, longer duration of breastfeeding, born in a later year, older maternal age and higher maternal education level were associated with both vitamin D and probiotics use. Shorter gestational age and mother not smoking during pregnancy were associated with a higher likelihood of probiotics supplementation only. CONCLUSIONS: Vitamin D and probiotics supplementations are popular in children 0-2 years old and are associated with common factors. Data documented here will allow evaluation of the relationship between early childhood dietary intake and the development of islet autoimmunity and progression to T1D.


Assuntos
Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/prevenção & controle , Suplementos Nutricionais , Predisposição Genética para Doença , Probióticos/administração & dosagem , Vitamina D/administração & dosagem , Adulto , Peso ao Nascer , Pré-Escolar , Diabetes Mellitus Tipo 1/sangue , Feminino , Finlândia , Alemanha , Humanos , Lactente , Masculino , Micronutrientes/administração & dosagem , Micronutrientes/sangue , Estudos Prospectivos , Fatores de Risco , Inquéritos e Questionários , Suécia , Estados Unidos , Vitamina D/sangue , Adulto Jovem
4.
Adv Clin Chem ; 79: 25-41, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28212713

RESUMO

Extracellular vesicles (EVs) are submicroscopic lipid vesicles secreted from cells and play significant roles in cell-to-cell communication by transporting varieties of cell signaling molecules like proteins, DNA, mRNA, and microRNA. Recent studies showed that EVs are highly correlated with cancer progression and metastasis. However, there are some difficulties in probing each vesicle using popular analytical methods because of their small sizes and heterogeneous origins. These obstacles may be overcome by using a novel approach that senses highly curved membrane and negatively charged membrane lipids. In this chapter, we highlight the basic biological concepts of EVs, isolation, and quantification methods, and recent advent of peptide probes for EVs.


Assuntos
Sondas Moleculares/química , Peptídeos/química , Exossomos/química
5.
Orthop Traumatol Surg Res ; 102(8): 1023-1028, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27865687

RESUMO

BACKGROUND: Risk factors for hemorrhage in patients with pelvic ring fracture have been widely reported. Because there are many risk factors, it is thought that prediction accuracy of hemorrhage in cases of pelvic ring fracture could be improved by using a scoring system. HYPOTHESIS: We investigated the risk factors for massive hemorrhage (MH) and created a novel predictive score of MH in pelvic ring fractures. MATERIAL AND METHODS: We retrospectively reviewed patients with pelvic ring fractures (Abbreviated Injury Score≥3 and age≥16 years) from January 2007 to June 2015. We excluded the cases that might have hemorrhage from other sites sufficient to require a blood transfusion. Massive hemorrhage was defined as hemorrhage requiring transfusion of≥6 red cell concentrate units within 24h of admission. RESULTS: The MH group included 27 patients and the non-MH group included 71 patients. Lactate level, AO/OTA classification and extravasation of computed tomography (CT) contrast fluid had a significantly higher risk as a result of multivariable analysis. The combined score using these risk factors according to their odds-adjusted ratios was created to predict for MH: lactate level>2.5-5.0 (mmol/L)=1 point,>5.0 (mmol/L)=2 points, partially stable (OA/OTA classification B1/B2/B3)=1 point, unstable (C1/C2/C3)=2 points, pelvic extravasation of contrast on CT=4 points. The AUC of the calculated score was 0.93 (95% CI: 0.89-0.98). CONCLUSION: The combined score using these risk factors according to their odds-adjusted ratios was created to predict MH and was an effective prediction score. LEVEL OF EVIDENCE: IV, retrospective study.


Assuntos
Fraturas Ósseas/complicações , Hemorragia/etiologia , Ossos Pélvicos/lesões , Escala Resumida de Ferimentos , Idoso , Área Sob a Curva , Transfusão de Sangue , Estudos de Casos e Controles , Meios de Contraste , Extravasamento de Materiais Terapêuticos e Diagnósticos/etiologia , Feminino , Fraturas Ósseas/classificação , Hemorragia/sangue , Hemorragia/terapia , Humanos , Ácido Láctico/sangue , Masculino , Pessoa de Meia-Idade , Curva ROC , Estudos Retrospectivos , Fatores de Risco , Tomografia Computadorizada por Raios X
6.
J Phys Condens Matter ; 26(21): 216004, 2014 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-24806439

RESUMO

Magnetic susceptibility and magnetization of the quasicrystal approximants Au-SM-R (SM = Si, Ge or Sn / R = Gd, Tb, Dy or Ho) are investigated. Ferromagnetic transitions are observed in all of these compounds, in contrast to the spin-glass behavior reported in similar compounds, Ag-In-R (R = Eu, Gd, Tb or Dy). Au-SM-Gd (SM = Si, Ge or Sn) exhibit a simple ferromagnetic transition at 22.5, 13 and 9 K, respectively, whereas Au-Si-(Tb, Dy or Ho) show indications of a canted ferromagnetic transition at 8.3, 5.9 and 3.8 K, respectively. The latter are attributed to a crystal electric field effect that is absent in the Gd-bearing compounds. The ferromagnetic behavior in Au-SM-R may be understood to be a consequence of the short R-R distances compared to those for Cd-R and Ag-In-R.


Assuntos
Elementos da Série dos Lantanídeos/química , Imãs/química , Cristalografia por Raios X , Disprósio/química , Germânio/química , Ouro/química , Hólmio/química , Modelos Químicos , Modelos Moleculares , Estrutura Molecular , Silício/química , Estrôncio/química , Térbio/química
7.
J Phys Chem B ; 118(7): 1932-42, 2014 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-24479531

RESUMO

The angular dependences of g-value and line width of EPR spectra of paramagnetic all-organic liquid crystalline (LC) materials were measured for the quantitative characterization of the nematic, cholesteric, and smectic C phases. The detailed molecular alignment in mesophases was determined by means of numerical spectra simulation focusing on spin exchange and dipole-dipole magnetic interactions of neighboring molecules. The obtained structural data indicate that the spin polarization mechanism between neighboring molecules rather than the direct through-space interactions between paramagnetic centers is responsible for the specific magnetic properties of the studied LC materials.

8.
J Mater Chem B ; 2(26): 4130-4133, 2014 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-32261745

RESUMO

Magnetically-transportable core-shell emulsion droplets with an antioxidative all-organic paramagnetic liquid shell [Nitroxide Radical Liquid (NRL) microcapsules] were demonstrated. We successfully fabricated stable NRL microcapsules with microfluidic devices. The NRL microcapsules are magnetically transportable and are likely to protect the inner phase from oxidants. Consequently, the NRL microcapsules can serve as a flexible antioxidative magnetic carrier for nanoliter cargoes.

9.
J Phys Condens Matter ; 25(42): 426004, 2013 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-24077450

RESUMO

Magnetic susceptibility and specific heat measurements on quasicrystalline approximants Au-Si-Gd and Au-Ge-Gd reveal that a ferromagnetic (FM) transition occurs at Tc = 22.5(5) K for Au-Si-Gd and at Tc = 13(1) K for Au-Ge-Gd, which are the first examples of ferromagnetism in crystalline approximants. In addition, a re-entrant spin-glass (RSG) transition is observed at TRSG = 3.3 K for Au-Ge-Gd in contrast to Au-Si-Gd. The different behaviors are understood based on the recent structural models reported by Gebresenbut et al (2013 J. Phys.: Condens. Matter 25 135402). The RSG transition in Au-Ge-Gd is attributed to a random occupation of the center of the Gd12 icosahedron by Gd atoms; a central Gd spin hinders the long-range FM order.

10.
J Phys Condens Matter ; 25(39): 395007, 2013 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-24018417

RESUMO

Scanning tunneling microscopy and x-ray photoemission spectroscopy on a polygrain icosahedral (i-) Al­Pd­Re quasicrystal (QC) show the formation of the twofold surfaces with symmetry and composition expected from the bulk. The predominant occurrence of the twofold surface on the polygrain i-QC having random grain orientation, as well as preferential formation of terrace edges, kinks and voids along the twofold axes, consistently indicates that the twofold surface, which has the highest atomic density, is the most stable among all the crystallographic planes.

11.
J Phys Condens Matter ; 24(29): 294207, 2012 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-22773390

RESUMO

We performed electrical resistivity ρ, magnetic susceptibility χ, specific heat C and electron diffraction measurements on single-crystalline samples of PrT2Zn20 (T = Ru, Rh and Ir). The three compounds show the Van Vleck paramagnetic behavior, indicating the nonmagnetic crystalline electric field (CEF) ground states. A Schottky-type peak appears at around 14 K, irrespective of the T element, which can be moderately reproduced by a doublet­triplet model. For T = Ru, a structural transition occurs at Ts = 138 K, below which no phase transition appears down to 0.04 K. On the other hand, for T = Ir, antiferroquadrupole (AFQ) ordering arising from the nonmagnetic Γ3 doublet takes place at TQ = 0.11 K. For T = Rh, despite a structural transition between 170 and 470 K, the CEF ground state is still the non-Kramers Γ3 doublet. However, no phase transition due to the Γ3 doublet was observed even down to 0.1 K.

12.
Curr Mol Med ; 12(5): 634-51, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22515981

RESUMO

The Growth Arrest and DNA Damage-inducible 45 (GADD45) proteins have been implicated in regulation of many cellular functions including DNA repair, cell cycle control, senescence and genotoxic stress. However, the pro-apoptotic activities have also positioned GADD45 as an essential player in oncogenesis. Emerging functional evidence implies that GADD45 proteins serve as tumor suppressors in response to diverse stimuli, connecting multiple cell signaling modules. Defects in the GADD45 pathway can be related to the initiation and progression of malignancies. Moreover, induction of GADD45 expression is an essential step for mediating anti-cancer activity of multiple chemotherapeutic drugs and the absence of GADD45 might abrogate their effects in cancer cells. In this review, we present a comprehensive discussion of the functions of GADD45 proteins, linking their regulation to effectors of cell cycle arrest, DNA repair and apoptosis. The ramifications regarding their roles as essential and central players in tumor growth suppression are also examined. We also extensively review recent literature to clarify how different chemotherapeutic drugs induce GADD45 gene expression and how its up-regulation and interaction with different molecular partners may benefit cancer chemotherapy and facilitate novel drug discovery.


Assuntos
Transformação Celular Neoplásica/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias/metabolismo , Animais , Apoptose/genética , Apoptose/fisiologia , Pontos de Checagem do Ciclo Celular/genética , Pontos de Checagem do Ciclo Celular/fisiologia , Transformação Celular Neoplásica/genética , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Neoplasias/genética , Proteínas GADD45
13.
Eur J Gynaecol Oncol ; 33(6): 648-51, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23327064

RESUMO

The authors report a case of granulosa cell tumor of the ovary that followed a rare clinical course, where the primary focus did not appear as a mass, and disseminated foci grew in the abdominal cavity. In 2008, a 70-year-old patient, gravida 6 and para 3, was diagnosed with a perihepatic mass, peritoneal dissemination, and an abdominal wall mass as confirmed by computed tomography (CT) scanning. There was no mass lesion in the pelvis. The pathological diagnosis based on the resected mass in the abdominal wall was malignant mesothelioma. During follow-up, abdominal bloating developed from April 2009. CT scans indicated growth of the intraperitoneal lesions. Therefore, the patient received two cycles of combination therapy with cisplatin and pemetrexed. The treatment was discontinued due to lack of efficacy. The intraperitoneal lesions grew but the clinical course was slow and inconsistent with that of malignant mesothelioma. Central pathological review was requested in April 2011, and a granulosa cell tumor was diagnosed. The patient was referred to the department for detailed examination and treatment. The patient underwent incision of the intraperitoneal tumors, simple total hysterectomy, bilateral salpingo-oophorectomy, and omentectomy. The final pathological diagnosis was normal-size adult-type granulosa cell tumor originating from the left ovary. It was a case of granulosa cell tumor without ovarian enlargement where growth of the metastatic foci was the major observation. As complete surgical resection was achieved and no additional therapy was given, the subject was followed on an outpatient basis and no recurrence was identified.


Assuntos
Parede Abdominal/patologia , Tumor de Células da Granulosa/patologia , Neoplasias Ovarianas/patologia , Neoplasias Peritoneais/secundário , Idoso , Feminino , Humanos
14.
J Viral Hepat ; 17(9): 618-23, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19889140

RESUMO

Hepatitis A virus (HAV) infection is still an important issue worldwide. A distinct set of viruses encode proteins that enhance viral cap-independent translation initiation driven by an internal ribosome entry site (IRES) and suppress cap-dependent host translation. Unlike cytolytic picornaviruses, replication of HAV does not cause host cell shut off, and it has been questioned whether HAV proteins interfere with its own and/or host translation. HAV proteins were coexpressed in Huh-7 cells with reporter genes whose translation was initiated by either cap-dependent or cap-independent mechanisms. Among the proteins tested, HAV proteinase 3C suppressed viral IRES-dependent translation. Furthermore, 3C cleaved the polypyrimidine tract-binding protein (PTB) whose interaction with the HAV IRES had been demonstrated previously. The combined results suggest that 3C-mediated cleavage of PTB might be involved in down-regulation of viral translation to give way to subsequent viral genome replication.


Assuntos
Cisteína Endopeptidases/metabolismo , Vírus da Hepatite A/fisiologia , Proteína de Ligação a Regiões Ricas em Polipirimidinas/metabolismo , Biossíntese de Proteínas , Proteínas Virais/metabolismo , Replicação Viral , Proteases Virais 3C , Linhagem Celular , Genes Reporter , Hepatócitos/virologia , Humanos
15.
Arch Virol ; 152(12): 2259-63, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17703289

RESUMO

Replication and transcription of the human respiratory syncytial virus (hRSV) genome is carried out by the ribonucleocapsid complex (RNA together with N, P, M2-1 and L proteins), with the L protein being responsible for all enzymatic activities. In the present study, we obtained anti-L polyclonal sera in mice. These antibodies were functional in immunofluorescence and Western blotting assays in hRSV-infected HEp-2 cells. In the immunofluorescence assays, we detected inclusion bodies in the anti-L staining, similar to the ones seen by anti-N or anti-P staining. The results presented here provide the first evidence of the intracellular localization of the hRSV L protein.


Assuntos
Corpos de Inclusão/metabolismo , Vírus Sincicial Respiratório Humano/metabolismo , Vírus Sincicial Respiratório Humano/patogenicidade , Proteínas Virais/metabolismo , Animais , Anticorpos Monoclonais/sangue , Anticorpos Monoclonais/imunologia , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Especificidade de Anticorpos , Western Blotting , Linhagem Celular , Imunofluorescência , Humanos , Corpos de Inclusão/virologia , Camundongos , Camundongos Endogâmicos BALB C , Vírus Sincicial Respiratório Humano/imunologia , Proteínas Virais/genética , Proteínas Virais/imunologia
16.
Neuroscience ; 143(2): 627-39, 2006 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-16979828

RESUMO

Anatomical connections of the insular cortex suggest its involvement in cognition, emotion, memory, and behavioral manifestation. However, there have been few neurophysiological studies on the insular cortex in primates, in relation to such higher cognitive functions. In the present study, neural activity was recorded from the monkey insular cortex during performance of a delayed-response delayed-reward go/nogo task. In this task, visual stimuli indicating go or nogo responses associated with reward (reward trials) and with no reward (no-reward trials) were presented after eye fixation. In the reward trials, the monkey was required to release a button during presentation of the 2nd visual stimuli after a delay period (delay 1). Then, a juice reward was delivered after another delay (delay 2). The results indicated that the neurons responding in each epoch of the task were topographically localized within the insular cortex, consistent with the previous anatomical studies indicating topographical distributions of afferent inputs from other subcortical and cortical sensory areas. Furthermore, some insular neurons 1) nonspecifically responded to the visual cues and during fixation; 2) responded to the visual cues predicting reward and during the delay period before reward delivery; 3) responded differentially in go/nogo trials during the delay 2; and 4) responded around button manipulation. The observed patterns of insular-neuron responses and the correspondence of their topographical localization to those in previous anatomical studies suggest that the insular cortex is involved in attention- and reward-related functions and might monitor and integrate activities of other brain regions during cognition and behavioral manifestation.


Assuntos
Córtex Cerebral/citologia , Comportamento de Escolha/fisiologia , Neurônios/fisiologia , Tempo de Reação/fisiologia , Recompensa , Análise de Variância , Animais , Comportamento Animal , Mapeamento Encefálico , Córtex Cerebral/fisiologia , Eletromiografia/métodos , Macaca mulatta , Neurônios/classificação
17.
Phys Rev Lett ; 92(14): 146402, 2004 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-15089561

RESUMO

Ca 2p-3d resonant photoemission spectroscopy of a Cd6Ca crystalline approximant unambiguously demonstrates that the low-lying unoccupied 3d levels of calcium are lowered below the Fermi energy by the formation of the approximant, as suggested from electronic structure calculations [Phys. Rev. Lett. 87, 206408 (2001)]]. Moreover, the Ca 3d partial density of states (DOS) obtained near the Fermi energy is in reasonable agreement with theoretical Ca 3d DOS. These results verify the unconventional picture that the origin of the pseudogap in the Cd-based quasicrystals is due to hybridization of the Ca 3d band with the Cd 5p band.

18.
J Int Med Res ; 32(1): 25-32, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-14997702

RESUMO

Co-stimulatory molecules play important roles in immune responses. We investigated the effect of Bu-Zhong-Yi-Qi-Tang (TJ-41) on the expression of intercellular adhesion molecule-1 (ICAM-1), B7.1 and B7.2 by peripheral blood mononuclear cells stimulated by interleukin-18 (IL-18) using fluorescence-activated cell sorter analysis. TJ-41 increased IL-18-induced ICAM-1 and B7.2 expression, resulting in enhanced production of tumour necrosis factor-alpha and interferon-gamma. These results suggest that TJ-41 enhances IL-18-induced cell-mediated immunity and may enhance host defence mechanisms against pathogens.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Interferon gama/biossíntese , Interleucina-1/farmacologia , Monócitos/efeitos dos fármacos , Fator de Necrose Tumoral alfa/biossíntese , Antígenos CD/metabolismo , Antígeno B7-2 , Citometria de Fluxo , Humanos , Molécula 1 de Adesão Intercelular/metabolismo , Lipopolissacarídeos/farmacologia , Glicoproteínas de Membrana/metabolismo , Monócitos/metabolismo
19.
Phys Rev Lett ; 90(22): 226401, 2003 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-12857327

RESUMO

We have found that the electronic transport of the binary icosahedral (i) Cd-Yb is extremely sensitive to a minute substitution of Mg for Cd atoms; the positive temperature coefficient of the resistivity (TCR) at low temperatures seen in the binary i Cd-Yb disappears by addition of only 0.1 at. % Mg and, moreover, the TCR stays negative well up to 60 at. % Mg. Such sensitiveness of the resistivity in the very dilute Mg concentration region, which is a consequence of the long coherence length (>28 A) of the conduction electrons in the quasiperiodic lattice, has led us to an unexpected conclusion: The negative TCR in the ternary i phase is due to partial chemical disorder; i.e., it is not a consequence of the quasiperiodicity.

20.
Am J Physiol Regul Integr Comp Physiol ; 284(4): R1108-18, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12511427

RESUMO

Activation of the renin-angiotensin system in the brain is considered important in the arousal and expression of sodium appetite. To clarify the effects of directly activating this hormonal cascade, taste neurons in the nucleus of the solitary tract of rats were tested with a battery of sapid stimuli after intracerebroventricular injection of renin or its vehicle. The rats were chronically prepared but lightly anesthetized during the recording procedure. Eighty-five taste neurons were tested: 46 after renin injections and 39 after vehicle. Neural activity was counted for 5.0-s periods without stimulation (spontaneous) and during stimulation with water and sapid chemicals. The averaged responses to each of the standard stimuli (0.1 M NaCl, 0.3 M sucrose, 0.01 M citric acid, and 0.01 M quinine hydrochloride) did not differ significantly between the two conditions. When the rats were tested with a concentration range of NaCl, however, after renin the average responses to the hypertonic 0.3 and 1.0 M stimuli were reduced to 74 and 70%, respectively, compared with those after vehicle injections. A similar tendency was evident for the subsample of neurons that responded best to NaCl, but the effect was smaller. These data are consistent with, but not as dramatic as, those reported after dietary-induced sodium appetite.


Assuntos
Renina/farmacologia , Núcleo Solitário/efeitos dos fármacos , Núcleo Solitário/fisiologia , Paladar/efeitos dos fármacos , Paladar/fisiologia , Animais , Apetite/efeitos dos fármacos , Ácido Cítrico/farmacologia , Ingestão de Líquidos/efeitos dos fármacos , Masculino , Vias Neurais/efeitos dos fármacos , Vias Neurais/fisiologia , Quinina/farmacologia , Ratos , Ratos Sprague-Dawley , Renina/administração & dosagem , Cloreto de Sódio/administração & dosagem , Cloreto de Sódio/farmacologia , Cloreto de Sódio/urina , Sacarose/administração & dosagem , Sacarose/farmacologia , Micção/efeitos dos fármacos , Água/administração & dosagem
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