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1.
J Med Syst ; 43(2): 21, 2018 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-30564924

RESUMO

In this paper, we propose a new Internet of Things (IoT) based predictive modelling by using fuzzy cluster based augmentation and classification for predicting the lung cancer disease through continuous monitoring and also to improve the healthcare by providing medical instructions. Here, the fuzzy clustering method is used and which is based on transition region extraction for effective image segmentation. Moreover, Fuzzy C-Means Clustering algorithm is used to categorize the transitional region features from the feature of lung cancer image. In this work, Otsu thresholding method is used for extracting the transition region from lung cancer image. Moreover, the right edge image and the morphological thinning operation are used for enhancing the performance of segmentation. In addition, the morphological cleaning and the image region filling operations are performed over an edge lung cancer image for getting the object regions. In addition, we also propose a new incremental classification algorithm which combines the existing Association Rule Mining (ARM), the standard Decision Tree (DT) with temporal features and the CNN. The experiments have been conducted by using the standard images that are collected from database and the current health data which are collected from patient through IoT devices. The results proved that the performance of the proposed prediction model which is able to achieve the better accuracy when it is compared with other existing prediction model.


Assuntos
Lógica Fuzzy , Interpretação de Imagem Assistida por Computador/métodos , Processamento de Imagem Assistida por Computador/métodos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/patologia , Algoritmos , Humanos
2.
Neuroscience ; 167(4): 1004-13, 2010 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-20302917

RESUMO

Strict control over the initiation of action potentials is the primary task of a neuron. One way to lose proper spike control is to create several spikes, a burst, when only one should be initiated. We describe a new site for burst initiation in rat hippocampal CA3 neurons: the Schaffer collateral axons. These axons lack myelin, are long, extremely thin, and form synapses along their entire paths, features typical for many, if not most cortical axons in the mammalian brain. We used hippocampal slices and recorded from individual Schaffer collateral axons. We found that single action potentials were converted into bursts of two to six action potentials after blocking 4-aminopyridine (4-AP) sensitive K(+) channels. The CA3 somata and initial part of their axons were surgically removed in these experiments, leading to the conclusion that the bursts were initiated far out in the axons. This conclusion was supported by two additional kinds of experiments. First, local application of 4-AP to one out of two stimulated axonal branches of the same neuron showed bursting only at the 4-AP exposed branch. Second, intracellular recordings from CA3 somata showed that some spontaneously occurring bursts were resistant to somatic hyperpolarization. We then investigated a hyperexcitable period that follows individual spikes in the Schaffer collaterals. With extracellular excitability testing, we showed that the time course of this hyperexcitability was compatible with that of the bursts, so this hyperexcitability could be the underlying cause of the bursts. Furthermore, the hyperexcitability was enhanced by low doses of 4-AP (20 microM), alpha-dendrotoxin (alpha-DTX) or margatoxin (MgTX). Kv1.2 containing channels may therefore dampen the hyperexcitability, but because bursting was observed only at high 4-AP concentration (1 mM), other channels may be needed to prevent axonal bursting.


Assuntos
Axônios/fisiologia , Região CA3 Hipocampal/fisiologia , Bainha de Mielina/fisiologia , 4-Aminopiridina/farmacologia , Potenciais de Ação , Animais , Axônios/efeitos dos fármacos , Venenos Elapídicos/farmacologia , Técnicas In Vitro , Canal de Potássio Kv1.2/antagonistas & inibidores , Canal de Potássio Kv1.2/fisiologia , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Ratos , Ratos Wistar , Venenos de Escorpião/farmacologia , Temperatura
3.
Auton Neurosci ; 137(1-2): 56-62, 2007 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-17716954

RESUMO

We examined the effects of two putative gap junction blockers, heptanol and carbenoxolone, on noradrenaline-induced contractions in guinea pig vas deferens. The force generated due to the exogenously added noradrenaline (20 microM) consisted of two components: the tonic and the oscillatory. 2 mM heptanol abolished the oscillatory contractions and drastically suppressed both the maximum force (by 85.4 +/- 18.2%) as well as the tonic component (by 28.8 +/- 5.1%) (P<0.01, n=7). However, the effects of carbenoxolone (50 microM) were strikingly different, with the spikes of the oscillatory component being merged into a steady, "fused" contraction, without affecting the maximum force developed. The L-type Ca(2+) channel blocker nifedipine (2 microM) abolished the oscillatory component of the contractions and significantly reduced the maximum force and tonic component (by 82.4 +/- 6.8% and 19.7 +/- 6.4% respectively; P<0.01, n=4), in a manner similar to that elicited by heptanol. Our results indicate that (i) while carbenoxolone specifically blocks gap junctions, heptanol appears to exert its actions through non-gap junctional mechanisms, possibly by blocking VGCCs in smooth muscle; (ii) gap junctions play a significant modulatory role in the generation of noradrenaline-induced contractions in guinea pig vas deferens, particularly in the emergence of oscillatory contractions, while the maximum force developed may be independent of gap junctional contribution.


Assuntos
Carbenoxolona/farmacologia , Heptanol/farmacologia , Contração Muscular/efeitos dos fármacos , Norepinefrina/farmacologia , Ducto Deferente/efeitos dos fármacos , Vasoconstritores/farmacologia , Animais , Bloqueadores dos Canais de Cálcio/farmacologia , Relação Dose-Resposta a Droga , Interações Medicamentosas , Cobaias , Masculino , Potenciais da Membrana/efeitos dos fármacos , Nifedipino/farmacologia , Ducto Deferente/fisiologia
4.
Naunyn Schmiedebergs Arch Pharmacol ; 374(3): 207-14, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17093918

RESUMO

The effects of the putative gap junction blocker carbenoxolone on smooth muscle syncytial properties and junction potentials were studied in guinea pig vas deferens (GPVD). Treatment with 50 muM carbenoxolone reversibly and significantly increased input resistance (R (in)) (by 682.5 +/- 326.0 %, P < 0.05) and abolished cable potentials within 6-7 mins of incubation, without disturbing resting membrane potential. Carbenoxolone reversibly and significantly increased the amplitude of spontaneous excitatory junction potentials (sEJPs) by 96.9 +/- 35.45% (P < 0.05), shifted their amplitude distribution rightwards, and reduced their frequency of occurrence by 58.17 +/- 17.7% (P < 0.05), without altering their time courses. Similarly, carbenoxolone increased the amplitude of evoked excitatory junction potentials (eEJPs) by 17.7 +/- 5.88% and tau (decay) by 19.43 +/- 8.29% (P < 0.05). Our results indicate that carbenoxolone alters the electrical properties and junctional potentials of the GPVD by a mechanism consistent with a relatively specific block of gap junctions. These results suggest that gap junction mediated cell-to-cell communication may significantly modulate the electrical properties and junctional potentials of the GPVD and consequently the physiological functioning of this tissue.


Assuntos
Carbenoxolona/farmacologia , Junções Comunicantes/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Ducto Deferente/efeitos dos fármacos , Animais , Comunicação Celular/efeitos dos fármacos , Eletrofisiologia , Potenciais Evocados/efeitos dos fármacos , Cobaias , Masculino , Potenciais da Membrana/efeitos dos fármacos , Músculo Liso/metabolismo , Transmissão Sináptica/efeitos dos fármacos , Ducto Deferente/fisiologia
5.
J Physiol Sci ; 56(1): 21-8, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16779910

RESUMO

This study examines the role of gap junctional communication in smooth muscle in relation to the frequency of stimulation and the innervation density of the tissue in the generation of neurogenic contractions. Toward this end the effects of heptanol, a gap junctional blocker, on the neurogenic contractions of guinea pig and rat vas deferens at different frequencies of stimulation (single pulse, 5, 10, 20, 40, 60, and 80 Hz) were studied. In both the prostatic and epididymal halves of these tissues, heptanol abolished the neurogenic contractions at the lower frequencies of stimulation. At higher frequencies, contractions were resistant to heptanol action. The effect of heptanol on the neurogenic contractions was found to decrease with increasing stimulation frequency. The neurogenic contractions of rat vas deferens were more resistant to heptanol than those of guinea pig vas deferens. Our data indicate that gap junctional communication is significant in the generation of neurogenic contractions in both guinea pig and rat vas deferens in a frequency-dependent manner, and we discuss the mechanisms underlying these findings.


Assuntos
Junções Comunicantes/fisiologia , Heptanol/farmacologia , Contração Muscular/fisiologia , Ducto Deferente/efeitos dos fármacos , Ducto Deferente/inervação , Animais , Comunicação Celular/efeitos dos fármacos , Comunicação Celular/fisiologia , Estimulação Elétrica , Epididimo/efeitos dos fármacos , Epididimo/inervação , Epididimo/fisiologia , Junções Comunicantes/efeitos dos fármacos , Cobaias , Masculino , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Músculo Liso/inervação , Músculo Liso/fisiopatologia , Próstata/efeitos dos fármacos , Próstata/inervação , Próstata/fisiologia , Ratos , Ratos Wistar , Fatores de Tempo , Ducto Deferente/fisiopatologia
6.
J Physiol ; 575(Pt 2): 469-80, 2006 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-16675493

RESUMO

At sites of purinergic neurotransmission, synaptic ecto-ATPase is believed to limit the actions of ATP following its neural release. However, details of the modulation by this enzyme of the ATP-mediated conductance change and the possible mechanisms mediating this modulation remain unelucidated. We have addressed these issues by studying the effect of ARL 67156, a selective ecto-ATPase inhibitor, on ATP-mediated electrical and contractile activity in the sympathetically innervated guinea-pig vas deferens. ARL 67156 at 100 mum significantly potentiated the amplitude of spontaneous excitatory junction potentials (SEJPs) by 81.1% (P < 0.01) and prolonged their time courses (rise time by 49.7%, decay time constant by 38.2%; P < 0.01). Moreover, the frequency of occurrence of SEJPs was strikingly increased (from 0.28 +/- 0.13 to 0.90 +/- 0.26 Hz; P < 0.01), indicating an additional, primarily presynaptic, effect of ecto-ATPase inhibition. The frequency of occurrence of discrete events (DEs), which represent nerve stimulation-evoked quantal release of neurotransmitter, was also increased ( approximately 6-fold; P < 0.01), along with the appearance of DEs at previously 'silent' latencies. Purinergic contractions of the vas deferens were potentiated significantly (P < 0.01) by ARL 67156; these potentiated contractions were suppressed by the A1 agonist adenosine (P < 0.01) but left unaffected by the A1 antagonist 8-phenyltheophylline (8-PT). Our results indicate (i) that ecto-ATPase activity, in addition to modulating the ATP-mediated postjunctional conductance change, may regulate transmitter release prejunctionally under physiological conditions, and (ii) that the prejunctional regulation may be mediated primarily via presynaptic P2X, rather than A1, receptors.


Assuntos
Potenciais de Ação/fisiologia , Adenosina Trifosfatases/antagonistas & inibidores , Junção Neuromuscular/fisiologia , Ducto Deferente/inervação , Ducto Deferente/fisiologia , Adenosina/farmacologia , Adenosina Trifosfatases/fisiologia , Trifosfato de Adenosina/análogos & derivados , Trifosfato de Adenosina/farmacologia , Trifosfato de Adenosina/fisiologia , Animais , Eletrofisiologia , Cobaias , Masculino , Contração Muscular/efeitos dos fármacos , Contração Muscular/fisiologia , Junção Neuromuscular/efeitos dos fármacos , Receptor A1 de Adenosina/fisiologia , Receptores Purinérgicos P2/fisiologia , Receptores Purinérgicos P2X , Transdução de Sinais/fisiologia , Transmissão Sináptica/fisiologia , Teofilina/análogos & derivados , Teofilina/farmacologia , Fatores de Tempo , Ducto Deferente/efeitos dos fármacos
7.
J Smooth Muscle Res ; 42(1): 49-61, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16702763

RESUMO

We have studied the effects of 1-heptanol and nifedipine on noradrenaline (NA)-induced contractions in order to explore the role of gap junctions and their interactions with L-type Ca2+ channel mediated [Ca2+]o entry in the generation of NA-induced contractions in the rat vas deferens. Application of 20 microM NA to rat vas deferens resulted in contractions with three different components, an initial phasic component followed by a tonic component overlapped with an oscillatory component. Heptanol (0.01-2 mM) induced a concentration dependent reduction of the contractions. 2 mM heptanol reduced the phasic component by 32.9 +/- 4.4% and the tonic component by 93.8 +/- 1.9% of control, while the oscillatory component was completely abolished (n=7). Nifedipine (2 microM) reduced the phasic component by 34.5 +/- 4.1% and the tonic component by 89.5 +/- 3.8% of control and abolished the oscillatory component (n=6). In the presence of heptanol and nifedipine together, the phasic component was reduced by 61.3 +/- 8.3% and the tonic component by 94.5 +/- 1.0% of control. The oscillatory component was completely abolished (n=6). These results allow the conclusion that phasic contraction is mainly due to the direct action of NA, independent of gap junctions, while the tonic and oscillatory contractions may depend significantly on cell-to-cell communication. These in turn may depend critically on the availability of extracellularly derived Ca2+.


Assuntos
Heptanol/farmacologia , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Norepinefrina/farmacologia , Ducto Deferente/efeitos dos fármacos , Animais , Cálcio/fisiologia , Canais de Cálcio Tipo T/fisiologia , Junções Comunicantes/efeitos dos fármacos , Junções Comunicantes/fisiologia , Masculino , Nifedipino/farmacologia , Ratos , Ratos Wistar
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