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1.
Cogn Process ; 25(3): 363-378, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38607468

RESUMO

It has been shown that reading the vowel [i] and consonant [t] facilitates precision grip responses, while [ɑ] and [k] are associated with faster power grip responses. A similar effect has been observed when participants perform responses with small or large response keys. The present study investigated whether the vowels and consonants could produce different effects with the grip responses and keypresses when the speech units are read aloud (Experiment 1) or silently (Experiment 2). As a second objective, the study investigated whether the recently observed effect, in which the upper position of a visual stimulus is associated with faster vocalizations of the high vowel and the lower position is associated with the low vowel, can be observed in manual responses linking, for example, the [i] with responses of the upper key and [ɑ] with lower responses. Firstly, the study showed that when the consonants are overtly articulated, the interaction effect can be observed only with the grip responses, while the vowel production was shown to systematically influence small/large keypresses, as well as precision/power grip responses. Secondly, the vowel [i] and consonant [t] were associated with the upper responses, while [ɑ] and [k] were associated with the lower responses, particularly in the overt articulation task. The paper delves into the potential sound-symbolic implications of these phonetic elements, suggesting that their acoustic and articulatory characteristics might implicitly align them with specific response magnitudes, vertical positions, and grip types.


Assuntos
Força da Mão , Fonética , Desempenho Psicomotor , Humanos , Masculino , Feminino , Adulto Jovem , Adulto , Força da Mão/fisiologia , Desempenho Psicomotor/fisiologia , Simbolismo , Leitura , Percepção da Fala/fisiologia
2.
J Environ Manage ; 308: 114640, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35124316

RESUMO

Due to the increasing demand for low carbon-footprint bioproducts in the markets, innovative processes technologies and products are needed. The objective of this study was to assess the quality and potential of food waste (FW) from the hospitality sector to produce volatile fatty acids (VFAs). A batch type acid fermentation system was used to study VFA production in different process conditions (a decreased pH and increased organic loading rate). The evolution of VFAs and long-chain fatty acids was followed. Amplicon sequencing of the 16S rRNA gene was used to investigate the bacterial and archaeal community, and elucidate microbial communities in different FW and process conditions. The results show that high VFA concentrations (of up to 18 g/L) were achieved in overloaded conditions, which were also affected by the activity and composition of the inoculum. FW played an important role in modulating microbial composition, especially the bacterial communities belonging to the lactic acid bacteria group.


Assuntos
Microbiota , Eliminação de Resíduos , Anaerobiose , Reatores Biológicos , Ácidos Graxos Voláteis , Fermentação , Alimentos , Concentração de Íons de Hidrogênio , Microbiota/genética , RNA Ribossômico 16S/genética , Esgotos
3.
Psychol Res ; 81(4): 827-839, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27306548

RESUMO

The shape and size-related sound symbolism phenomena assume that, for example, the vowel [i] and the consonant [t] are associated with sharp-shaped and small-sized objects, whereas [ɑ] and [m] are associated with round and large objects. It has been proposed that these phenomena are mostly based on the involvement of articulatory processes in representing shape and size properties of objects. For example, [i] might be associated with sharp and small objects, because it is produced by a specific front-close shape of articulators. Nevertheless, very little work has examined whether these object properties indeed have impact on speech sound vocalization. In the present study, the participants were presented with a sharp- or round-shaped object in a small or large size. They were required to pronounce one out of two meaningless speech units (e.g., [i] or [ɑ]) according to the size or shape of the object. We investigated how a task-irrelevant object property (e.g., the shape when responses are made according to size) influences reaction times, accuracy, intensity, fundamental frequency, and formant 1 and formant 2 of vocalizations. The size did not influence vocal responses but shape did. Specifically, the vowel [i] and consonant [t] were vocalized relatively rapidly when the object was sharp-shaped, whereas [u] and [m] were vocalized relatively rapidly when the object was round-shaped. The study supports the view that the shape-related sound symbolism phenomena might reflect mapping of the perceived shape with the corresponding articulatory gestures.


Assuntos
Percepção Espacial/fisiologia , Percepção da Fala/fisiologia , Simbolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
4.
Phys Chem Chem Phys ; 18(6): 4266-94, 2016 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-26804321

RESUMO

Nonlinear optical frequency conversion is one of the most versatile methods to generate wavelength-tunable laser light in the mid-infrared region. This spectral region is particularly important for trace gas detection and other applications of molecular spectroscopy, because it accommodates the fundamental vibrational bands of several interesting molecules. In this article, we review the progress of the most significant nonlinear optics instruments for widely tunable, high-resolution mid-infrared spectroscopy: continuous-wave optical parametric oscillators and difference frequency generators. We extend our discussion to mid-infrared optical frequency combs, which are becoming increasingly important spectroscopic tools, owing to their capability of highly sensitive and selective parallel detection of several molecular species. To illustrate the potential and limitations of mid-infrared sources based on nonlinear optics, we also review typical uses of these instruments in both applied and fundamental spectroscopy.

5.
J Chem Phys ; 144(24): 244201, 2016 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-27369508

RESUMO

A novel mid-infrared/near-infrared double resonant absorption setup for studying infrared-inactive vibrational states is presented. A strong vibrational transition in the mid-infrared region is excited using an idler beam from a singly resonant continuous-wave optical parametric oscillator, to populate an intermediate vibrational state. High output power of the optical parametric oscillator and the strength of the mid-infrared transition result in efficient population transfer to the intermediate state, which allows measuring secondary transitions from this state with a high signal-to-noise ratio. A secondary, near-infrared transition from the intermediate state is probed using cavity ring-down spectroscopy, which provides high sensitivity in this wavelength region. Due to the narrow linewidths of the excitation sources, the rovibrational lines of the secondary transition are measured with sub-Doppler resolution. The setup is used to access a previously unreported symmetric vibrational state of acetylene, ν1+ν2+ν3+ν4 (1)+ν5 (-1) in the normal mode notation. Single-photon transitions to this state from the vibrational ground state are forbidden. Ten lines of the newly measured state are observed and fitted with the linear least-squares method to extract the band parameters. The vibrational term value was measured to be at 9775.0018(45) cm(-1), the rotational parameter B was 1.162 222(37) cm(-1), and the quartic centrifugal distortion parameter D was 3.998(62) × 10(-6) cm(-1), where the numbers in the parenthesis are one-standard errors in the least significant digits.

6.
Opt Lett ; 40(7): 1342-5, 2015 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-25831328

RESUMO

Monitoring of radiocarbon (C14) in carbon dioxide is demonstrated using mid-infrared spectroscopy and a quantum cascade laser. The measurement is based on cavity ring-down spectroscopy, and a high sensitivity is achieved with a simple setup. The instrument was tested using a standardized sample containing elevated levels of radiocarbon. Radiocarbon dioxide could be detected from samples with an isotopic ratio C14/C as low as 50 parts-per-trillion, corresponding to an activity of 5 kBq/m(3) in pure CO(2), or 2 Bq/m(3) in air after extraction of the CO(2) from an air sample. The instrument is simple, compact, and robust, making it the ideal tool for on-site measurements. It is aimed for monitoring radioactive gaseous emissions in a nuclear power environment, during the operation and decommissioning of nuclear power plants. Its high sensitivity also makes it the ideal tool for the detection of leaks in radioactive waste repositories.

7.
Exp Brain Res ; 232(7): 2359-68, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24710666

RESUMO

It has been proposed that articulatory gestures are shaped by tight integration in planning mouth and hand acts. This hypothesis is supported by recent behavioral evidence showing that response selection between the precision and power grip is systematically influenced by simultaneous articulation of a syllable. For example, precision grip responses are performed relatively fast when the syllable articulation employs the tongue tip (e.g., [te]), whereas power grip responses are performed relatively fast when the syllable articulation employs the tongue body (e.g., [ke]). However, this correspondence effect, and other similar effects that demonstrate the interplay between grasping and articulatory gestures, has been found when the grasping is performed during overt articulation. The present study demonstrates that merely reading the syllables silently (Experiment 1) or hearing them (Experiment 2) results in a similar correspondence effect. The results suggest that the correspondence effect is based on integration in planning articulatory gestures and grasping rather than requiring an overt articulation of the syllables. We propose that this effect reflects partially overlapped planning of goal shapes of the two distal effectors: a vocal tract shape for articulation and a hand shape for grasping. In addition, the paper shows a pitch-grip correspondence effect in which the precision grip is associated with a high-pitched vocalization of the auditory stimuli and the power grip is associated with a low-pitched vocalization. The underlying mechanisms of this phenomenon are discussed in relation to the articulation-grip correspondence.


Assuntos
Gestos , Força da Mão/fisiologia , Percepção da Fala/fisiologia , Estimulação Acústica , Adulto , Análise de Variância , Feminino , Humanos , Masculino , Boca , Tempo de Reação/fisiologia , Leitura , Adulto Jovem
8.
BJOG ; 120(1): 64-74, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23126307

RESUMO

OBJECTIVE: To study the effect of aspirin in the prevention of pre-eclampsia in high-risk women. DESIGN: Randomised, double-blinded, placebo-controlled trial. SETTING: Maternity clinics in ten Finnish hospitals participating in the PREDO Project. SAMPLE: A total of 152 women with risk factors for pre-eclampsia and abnormal uterine artery Doppler velocimetry. METHODS: Participants were randomised to start either aspirin 100 mg/day or placebo at 12 + 0 to 13 + 6 weeks + days of gestation. Because of the limited power of this trial, we also conducted a meta-analysis of randomised controlled trials that included data on 346 women with abnormal uterine artery Doppler flow velocimetry, and aspirin 50-150 mg/day started at or before 16( ) weeks of gestation. MAIN OUTCOME MEASURE: Pre-eclampsia, gestational hypertension and birthweight standard deviation (SD) score. Outcome measures for the meta-analysis were pre-eclampsia, severe pre-eclampsia, preterm (diagnosed <37 + 0 weeks of gestation) and term pre-eclampsia. RESULTS: From the 152 randomised women, 121 were included in the final analysis. Low-dose aspirin did not reduce the rate of pre-eclampsia (relative risk [RR] 0.7, 95% CI 0.3-1.7); gestational hypertension (RR 1.6, 95% CI 0.6-4.2); early-onset pre-eclampsia (diagnosed <34 + 0 weeks of gestation) (RR 0.2, 95% CI 0.03-2.1); or severe pre-eclampsia (RR 0.4, 95% CI 0.1-1.3); and the results were not statistically significant in an intention-to-treat analysis. However, our meta-analysis, including the current data, suggested that low-dose aspirin initiated before 16 weeks of gestation reduces the risk of pre-eclampsia (RR 0.6, 95% CI 0.4-0.8) and severe pre-eclampsia (RR 0.3, 95% CI 0.1-0.7). CONCLUSIONS: Our trial showed no statistically significant effect of aspirin in preventing pre-eclampsia in high-risk women. However, our meta-analysis suggested that aspirin may reduce the incidence of pre-eclampsia.


Assuntos
Aspirina/uso terapêutico , Inibidores da Agregação Plaquetária/uso terapêutico , Pré-Eclâmpsia/prevenção & controle , Adolescente , Adulto , Método Duplo-Cego , Feminino , Finlândia , Humanos , Pré-Eclâmpsia/diagnóstico por imagem , Gravidez , Gravidez de Alto Risco , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento , Ultrassonografia Doppler em Cores , Adulto Jovem
9.
J Mot Behav ; 51(2): 129-140, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-29522383

RESUMO

The study investigated whether number magnitude can influence vocal responses. Participants produced either short or long version of the vowel [ɑ] (Experiment 1), or high or low-pitched version of that vowel (Experiment 2), according to the parity of a visually presented number. In addition to measuring reaction times (RT) of vocal responses, we measured the intensity, the fundamental frequency (f0) and the first and second formants of the vocalization. The RTs showed that the long and high-pitched vocal responses were associated with large numbers, while short and low-pitched vocal responses were associated with small numbers. It was also found that high-pitched vocalizations were mapped with the odd numbers, while the low-pitched vocalizations were mapped with the even numbers. Finally, large numbers increased the f0 values. The study shows systematic interactions between the processes that represent number magnitude and produce vocal responses.


Assuntos
Matemática , Comportamento Verbal , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estimulação Luminosa , Tempo de Reação , Adulto Jovem
11.
Acta Physiol (Oxf) ; 220(1): 28-35, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-27496203

RESUMO

AIM: We studied whether available oxygen without induced mechanical stretch regulates the release of the biologically active B-type natriuretic peptide (BNP) from Langendorff heart. METHODS: Rat hearts were isolated and perfused with a physiological Krebs-Henseleit solution at a constant hydrostatic pressure in Langendorff set-up. The basal O2 level of perfusate (24.4 ± 0.04 mg L-1 ) was gradually lowered to 3.0 ± 0.01 mg L-1 over 20 min using N2 gas (n = 7). BNP and O2 level were measured from coronary flow. During control perfusions (n = 5), the O2 concentration was kept at 26.6 ± 0.3 mg L-1 . RESULTS: A low oxygen concentration in the perfusate was associated with a significant increase in BNP release (F = 40.4, P < 0.001). Heart rate decreased when the oxygen concentration in the perfusate reached 9.1 ± 0.02 mg L-1 and continued to fall in lower oxygen concentrations (F = 14.8, P < 0.001). There was also a significant but inverse correlation between BNP and oxygen in the coronary flow (R2  = 0.27, P < 0.001). CONCLUSION: In the spontaneously beating Langendorff rat heart, a decreasing concentration of oxygen in the ingoing perfusion increased the secretion of BNP. The effect of oxygen was independent of mechanical stretch of the heart as it occurred even when the heart rate decreased but the pressure conditions remained constant. The difference in the oxygen capacitance of blood and Krebs-Henseleit solution appears to be a major factor affecting secretion of BNP, which is correlated with the oxygen tension of myocardial cells and affected both by the oxygen concentration and capacitance of solution perfusing the heart and by the coronary flow.


Assuntos
Hipóxia/metabolismo , Miocárdio/metabolismo , Peptídeo Natriurético Encefálico/metabolismo , Animais , Coração/metabolismo , Preparação de Coração Isolado , Masculino , Ratos , Ratos Sprague-Dawley
12.
Endocrinology ; 138(10): 4049-57, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9322911

RESUMO

Sphingosine 1-phosphate (SPP) potently mobilizes sequestered calcium and is a mitogen in several cell types. In the present investigation, we have evaluated the effect of SPP on intracellular free calcium concentration ([Ca2+]i) and synthesis of DNA in thyroid FRTL-5 cells. SPP rapidly and transiently mobilized sequestered calcium and stimulated entry of extracellular calcium. The entry of calcium, but not the mobilization, was in part inhibited by pretreatment with pertussis toxin (Ptx), and by activation of protein kinase C. SPP did not stimulate the production of inositol 1,4,5-trisphosphate. SPP stimulated the incorporation of 3H-thymidine in a time- and dose-dependent manner. The effect was not inhibited by Ptx. Furthermore, SPP stimulated the activation of the proto-oncogene c-fos. SPP rapidly tyrosine-phosphorylated an approximately 66 kDa protein. This phosphorylation persisted for at least 1 h. Pretreatment of the cells with genistein abolished the SPP-evoked tyrosine phosphorylation, and attenuated the SPP-evoked increase in [Ca2+]i. Furthermore, the SPP-evoked activation of Na+-H+ exchange was inhibited by genistein. The phosphorylation was not attenuated by pretreatment of the cells with Ptx. SPP per se did not affect cellular cAMP levels but attenuated the TSH-evoked increase in cAMP. As the effect of SPP might be due to activation of phospholipase D, we tested whether phosphatidic acid (PA) mobilized calcium or stimulated the incorporation of 3H-thymidine. PA mobilized sequestered calcium but did not stimulate calcium entry. PA very modestly enhanced the incorporation of 3H-thymidine. Our results suggest, that SPP stimulates DNA synthesis and activates entry of calcium in FRTL-5 cells. The effect on calcium entry appears to be dependent, at least in part, on one or several tyrosine kinases.


Assuntos
Cálcio/metabolismo , DNA/biossíntese , Lisofosfolipídeos , Esfingosina/análogos & derivados , Glândula Tireoide/citologia , Glândula Tireoide/metabolismo , Animais , Ácido Araquidônico/metabolismo , Sequência de Bases , Cálcio/análise , Linhagem Celular , AMP Cíclico/análise , AMP Cíclico/metabolismo , DNA/análise , DNA/genética , Primers do DNA/análise , Primers do DNA/química , Primers do DNA/genética , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Genisteína , Concentração de Íons de Hidrogênio , Inositol 1,4,5-Trifosfato/metabolismo , Isoflavonas/farmacologia , Toxina Pertussis , Reação em Cadeia da Polimerase , Proteínas Tirosina Quinases/fisiologia , Proteínas Proto-Oncogênicas c-fos/análise , Proteínas Proto-Oncogênicas c-fos/genética , Ratos , Esfingosina/farmacologia , Timidina/metabolismo , Glândula Tireoide/química , Fatores de Tempo , Trítio/metabolismo , Fatores de Virulência de Bordetella/farmacologia
13.
Br J Pharmacol ; 130(2): 471-7, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10807688

RESUMO

The effect of thyrotropin (TSH), on adenosine A(1) receptor expression in thyroid FRTL-5 cells was examined by [(3)H]-1, 3-dipropyl-,8-cyclopentyl xanthine ([(3)H]-DPCPX) binding on cells in suspension and on membrane preparation, and by in situ mRNA labelling. The estimated K(D) for intact cells was 0.19 nM and about 47,000 binding sites per cell were found in cells constantly grown in the presence of TSH. Three days deprivation of TSH decreased the number of [(3)H]-DPCPX binding sites without any significant effect of K(D). Reintroduction of TSH to the cells returned the higher level of A(1) receptors both in suspension binding studies on whole cells and on membrane preparations. In situ hybridization revealed that TSH evoked an increase in the number of cells densely labelled with a probe against A(1) receptor mRNA. The potency of the A(1) receptor agonist N(6)-cyclohexyladenosine (CHA) as an inhibitor of cyclic AMP formation induced by forskolin was increased in TSH-treated cells, with a shift in the IC(50) from 2.05 nM in TSH-deprived cells to 0.14 nM in TSH-treated cells. Since the activation of A(1) receptors inhibits TSH-mediated cyclic AMP signalling, our results suggest a regulatory feedback mechanism between signalling via adenosine A(1) receptors and TSH receptors.


Assuntos
Receptores Purinérgicos P1/biossíntese , Timo/efeitos dos fármacos , Tireotropina/farmacologia , Adenilil Ciclases/metabolismo , Animais , Sítios de Ligação , Células Cultivadas , Antagonistas de Receptores Purinérgicos P1 , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/metabolismo , Ratos , Transdução de Sinais , Timo/metabolismo , Trítio , Xantinas/farmacologia
14.
Brain Res Cogn Brain Res ; 7(3): 357-69, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9838192

RESUMO

Event-related brain potentials (ERP) were recorded to infrequent changes of a synthesized vowel (standard) to another vowel (deviant) in speakers of Hungarian and Finnish language, which are remotely related to each other with rather similar vowel systems. Both language groups were presented with identical stimuli. One standard-deviant pair represented an across-vowel category contrast in Hungarian, but a within-category contrast in Finnish, with the other pair having the reversed role in the two languages. Both within- and across-category contrasts elicited the mismatch negativity (MMN) ERP component in the native speakers of either language. The MMN amplitude was larger in across- than within-category contrasts in both language groups. These results suggest that the pre-attentive change-detection process generating the MMN utilized both auditory (sensory) and phonetic (categorical) representations of the test vowels.


Assuntos
Atenção/fisiologia , Córtex Auditivo/fisiologia , Memória/fisiologia , Fonética , Percepção da Fala/fisiologia , Estimulação Acústica , Adolescente , Adulto , Encéfalo/fisiologia , Variação Contingente Negativa/fisiologia , Eletroencefalografia , Feminino , Humanos , Idioma , Masculino
15.
Eur J Pharmacol ; 390(1-2): 43-50, 2000 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-10708705

RESUMO

The effect of adenosine A(1) receptor activation on the ATP-induced increase in intracellular free Ca(2+) was studied in control and protein kinase C down-regulated Fisher rat thyroid (FRTL-5) cells. Long-term phorbol ester treatment, which leads to protein kinase C down-regulation, enhanced the ATP-evoked extracellular Ca(2+) influx. The increased Ca(2+) influx was antagonized by the adenosine A(1) receptor antagonist 8-cyclopentyl-1, 3-dipropylxanthine (DPCPX). [3H]DPCPX binding studies revealed that phorbol ester-treatment increased the number of adenosine A(1) receptors. The adenosine A(1) receptor-mediated inhibition of the cyclic AMP formation was not affected by the increased receptor number. We conclude that the enhanced ATP-evoked Ca(2+) influx in protein kinase C down-regulated cells is mediated by adenosine formed by hydrolysis of ATP, and that this adenosine interacts with the increased number of A(1) receptors. The mechanism by which adenosine enhances Ca(2+) entry is not known. Thus, the larger number of adenosine A(1) receptors broadens the spectrum of adenosine A(1) receptor affected signaling systems in FRTL-5 cells.


Assuntos
Trifosfato de Adenosina/farmacologia , Cálcio/metabolismo , Receptores Purinérgicos P1/fisiologia , Glândula Tireoide/metabolismo , Adenosina Desaminase/metabolismo , Inibidores de Adenilil Ciclases , Animais , Linhagem Celular , Meios de Cultura , Regulação para Baixo/genética , Inibidores Enzimáticos/farmacologia , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/metabolismo , Proteína Quinase C/genética , Proteína Quinase C/metabolismo , Antagonistas de Receptores Purinérgicos P1 , Ensaio Radioligante , Ratos , Receptores Purinérgicos P1/efeitos dos fármacos , Glândula Tireoide/efeitos dos fármacos , Glândula Tireoide/enzimologia , Fatores de Virulência de Bordetella/farmacologia , Xantinas/farmacologia
16.
Acta Otolaryngol ; 114(5): 501-9, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7825431

RESUMO

Electromagnetically induced auditory perception was investigated in 18 deaf patients who were candidates for cochlear implants. In the extracranial magnetic stimulation (EMS) procedure, patients were stimulated with time-varying magnetic field brief pulses from a coil positioned at the i) auricle, ii) the mastoid, and iii) the temporal lobe area. EMS elicited auditory sensations in 26 ears (of 14 patients/subjects). The lowest threshold of auditory sensation (TAS) was found to be at the 20% EMS level, with a range of 20-50% of the maximum level (2.0 Tesla), and approximately equal sensitivity in each coil position. Eleven of the subjects hearing EMS-induced sound perceived changes in pitch while 6 heard "clicks" or clicks and tones. Spearman Rho correlation analysis showed a mild negative correlation between the EMS/TAS and the pre-implant FFA, best tone threshold (BTT), and direct promontorial electrical stimulation (ES) thresholds at 250 Hz and 500 Hz. No correlation was found between EMS or ES and performance on the pre-implant or post-implant psychacoustic tests (MAC VIII or 3-Digit speech tests) or the measurements of the thickness of cutaneous and osseous tissue from the stimulation sites at the mastoid and ear canal to the cochlear and 8th nerve. A fair positive correlation was found between the EMS/TAS and the post-implant (6 months) ES threshold when the electrodes allocated the 500 Hz frequency range were stimulated. A mild positive correlation between the pre-cochlear-implant promontorial electrical stimulation (ES) at 250 Hz and the four frequency tone average (FFA: 0.5, 1, 2, 4 kHz) was also found.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Percepção Auditiva/fisiologia , Campos Eletromagnéticos , Adolescente , Adulto , Idoso , Limiar Auditivo/fisiologia , Implantes Cocleares , Nervo Coclear/diagnóstico por imagem , Nervo Coclear/fisiopatologia , Surdez/diagnóstico por imagem , Surdez/fisiopatologia , Surdez/terapia , Estimulação Elétrica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estimulação Física/instrumentação , Estimulação Física/métodos , Tomografia Computadorizada por Raios X , Nervo Vestibulococlear/diagnóstico por imagem , Nervo Vestibulococlear/fisiopatologia
18.
Eur J Neurosci ; 23(9): 2538-41, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16706861

RESUMO

In 'quantity-languages', such as Japanese or Finnish, sound duration is linguistically relevant. We showed that quantity-language speakers were superior to speakers of a non-quantity language in discriminating the duration of even non-speech sounds. In contrast, there was no group difference in the discrimination of sound frequency. This result, obtained both by behavioural and neural indices at attentive and automatic levels of processing, indicates precise feature-specific tuning of the auditory-cortex functions by the mother tongue.


Assuntos
Córtex Auditivo/fisiologia , Mapeamento Encefálico , Idioma , Som , Percepção da Fala/fisiologia , Estimulação Acústica/métodos , Adulto , Discriminação Psicológica/fisiologia , Eletroencefalografia/métodos , Potenciais Evocados Auditivos/fisiologia , Feminino , Humanos , Masculino
19.
J Cell Physiol ; 171(3): 336-42, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9180903

RESUMO

Adenosine has been shown to modulate cell proliferation in FRTL-5 thyroid cells, although the mechanisms by which this interaction occurs is still unclear. In the present study we investigated the effects of adenosine on the 3H-thymidine incorporation, cell cycle kinetics, and expression of the transcription factor c-Fos in cells stimulated via three different mitogenic pathways, i.e., by thyroid stimulating hormone (TSH) [adenosine 3',5'-cyclic monophosphate(cAMP)], insulin (tyrosine kinase), or phorbol 12-myristate 13-acetate (protein kinase C). Addition of adenosine to cells grown in medium containing hormones and serum did not inhibit the incorporation of 3H-thymidine. If adenosine was added to hormone-deprived cells together with any of the tested mitogens, the stimulation of the 3H-thymidine incorporation was inhibited in a dose-dependent manner. The inhibition was significantly lower when the cells were preincubated with TSH or insulin for 48 h. Flow cytometric studies showed that adenosine evoked an inhibition of the cells in the G0/G1 phase. Submaximal doses of adenosine (10 nM-10 microM) were able to induce c-Fos expression in FRTL-5 cells. However, the mitogen-induced expression of c-Fos was not reduced by maximal dose of adenosine (100 microM). The effect of adenosine on DNA synthesis was not dependent on pertussis toxin-sensitive G-proteins. In addition, adenosine A1- or A2- receptor antagonists did not block the effect of adenosine. The effect of adenosine was abolished by treatment of the cells with adenosine deaminase, suggesting that the observed effect was not mediated by a metabolite of adenosine. The results suggest that adenosine is an effective blocker of mitogen-evoked DNA synthesis of FRTL-5 cells, provided that adenosine is administered simultaneously with the mitogen.


Assuntos
Adenosina/farmacologia , Replicação do DNA/efeitos dos fármacos , Insulina/farmacologia , Acetato de Tetradecanoilforbol/farmacologia , Glândula Tireoide/metabolismo , Tireotropina/farmacologia , Animais , Células Cultivadas , Antagonismo de Drogas , Ratos
20.
J Cell Physiol ; 169(3): 538-43, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8952703

RESUMO

The aim of the present study was to investigate the mechanisms regulating endothelin-1 (ET-1) secretion in rat thyroid FRTL-5 cells. ET-1 was found to be secreted after stimulation with adenosine and ATP. The release of ET-1 was sensitive to pertussis toxin, indicating a role of G-proteins in the stimulus-secretion coupling. The stimulation evoked by ATP or adenosine was inhibited by the P1-receptor antagonist 8-cyclopentyl-1,3-dipropylxanthine (DPCPX), and in the presence of adenosine deaminase the adenosine- and ATP-mediated ET-1 secretion was abolished. These evidences suggest a role of a P1-adenosine receptor in the secretion of ET-1. Increasing cyclic AMP with forskolin decreased the adenosine-mediated secretion. In addition, the intracellular calcium chelator BAPTA or inhibition of calcium entry with Ni2+ prevented the response. Protein kinase C (PKC) is also partly involved in ET-1 secretion in FRTL-5 cells. Activation of PKC with the phorbol ester phorbol 12-myristate 13-acetate (PMA) stimulated the secretion of ET-1 in a time- and dose-dependent manner. Furthermore, downregulation of PKC decreased the secretion of ET-1 stimulated by adenosine. In conclusion, ET-1 secretion in FRTL-5 cells is stimulated via a pertussis toxin-sensitive P1-receptor pathway which is modulated by several signal transduction mechanisms including cAMP, Ca2+, and PKC.


Assuntos
Trifosfato de Adenosina/farmacologia , Adenosina/farmacologia , Endotelina-1/metabolismo , Agonistas do Receptor Purinérgico P1 , Adenosina Desaminase/farmacologia , Animais , Cálcio/fisiologia , Linhagem Celular , AMP Cíclico/fisiologia , GMP Cíclico/fisiologia , Ativação Enzimática , Óxido Nítrico/fisiologia , Proteína Quinase C/fisiologia , Ratos , Receptores Purinérgicos P1/fisiologia , Taxa Secretória/efeitos dos fármacos , Transdução de Sinais , Glândula Tireoide , Xantinas/farmacologia
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