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1.
Pediatr Allergy Immunol ; 32(6): 1190-1196, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33894077

RESUMO

BACKGROUND: Childhood asthma is a common chronic disease that likely has prenatal origins. Gestational diabetes alters maternal physiology and may influence fetal risk for childhood-onset disease. However, the association between gestational diabetes and child asthma is not well characterized. OBJECTIVE: To investigate the association between gestational diabetes and wheeze/asthma at approximately 4 years of age in a racially diverse US cohort. METHODS: We studied mother-child dyads enrolled prenatally in the Conditions Affecting Neurocognitive Development and Learning in Early Childhood study. Gestational diabetes was determined by medical chart review. At approximately 4 years of age, we assessed child respiratory outcomes including parent report of physician-diagnosed asthma (ever), current wheeze (symptoms within the past 12 months), and current asthma (physician diagnosis and/or medication or symptoms within the past 12 months). We used the modified Poisson regression to assess associations between gestational diabetes and child respiratory outcomes, adjusting for maternal age, race, prenatal smoking, pre-pregnancy body mass index, parity, asthma history, socioeconomic status, and infant sex. RESULTS: Among 1107 women, 66% were African American/Black. Six percent (n = 62) had gestational diabetes documented during pregnancy. Gestational diabetes was associated with increased risk of physician-diagnosed asthma (adjusted risk ratio (RR) [95% Confidence Interval]: 2.13 [1.35, 3.38]; prevalence: 14%), current wheeze (RR: 1.85 [1.23, 2.78]; prevalence: 19%), and current asthma (RR: 2.01 [1.30, 3.10]; prevalence: 16%). CONCLUSIONS: Gestational diabetes was associated with increased risk of asthma and wheeze outcomes. Additional studies are needed to elucidate modifiable pathways underlying this association.


Assuntos
Asma , Diabetes Gestacional , Efeitos Tardios da Exposição Pré-Natal , Asma/epidemiologia , Pré-Escolar , Estudos de Coortes , Diabetes Gestacional/epidemiologia , Feminino , Humanos , Lactente , Gravidez , Efeitos Tardios da Exposição Pré-Natal/epidemiologia , Sons Respiratórios
2.
Bioelectrochemistry ; 112: 9-15, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27398978

RESUMO

A memristor is a resistor with memory that exhibits a pinched hysteretic relationship in cyclic voltammetry. Recently, we have found memristors in the electrical circuitry of plants and seeds. There are no publications in literature about the possible existence of memristors and electrical differentiators in fruits. Here we found that the electrostimulation of Golden Delicious or Arkansas Black apple fruits by bipolar periodic waves induces hysteresis loops with pinched points in cyclic voltammograms at low frequencies between 0.1MHz and 1MHz. At high frequencies of 1kHz, the pinched hysteresis loop transforms to a non-pinched hysteresis loop instead of a single line I=V/R for ideal memristors because the amplitude of electrical current depends on capacitance of a fruit's tissue and electrodes, frequency and direction of scanning. Electrostimulation of electrical circuits in apple fruits by periodic voltage waves also induces electrotonic potential propagation due to cell-to-cell electrical coupling with electrical differentiators. A differentiator is an electrical circuit in which the output of the circuit is approximately directly proportional to the rate of change of the input. The information gained from electrostimulation can be used to elucidate and to observe electrochemical and electrophysiological properties of electrical circuits in fruits.


Assuntos
Frutas/química , Malus/química , Impedância Elétrica , Eletroquímica , Frutas/efeitos dos fármacos , Especificidade da Espécie , Tetraetilamônio/farmacologia
3.
Plant Signal Behav ; 9(3): e28152, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24556876

RESUMO

We investigated electrical circuitry of the Venus flytrap, Mimosa pudica and Aloe vera. The goal was to discover if these plants might have a new electrical component--a resistor with memory. This element was postulated recently and the researchers were looking for its presence in different systems. The analysis was based on cyclic current-voltage characteristic where the resistor with memory should manifest itself. We found that the electrostimulation of plants by bipolar sinusoidal or triangle periodic waves induces electrical responses in the Venus flytrap, Mimosa pudica and Aloe vera with fingerprints of memristors. Tetraethylammonium chloride, an inhibitor of voltage gated K(+) channels, transforms a memristor to a resistor in plant tissue. Our results demonstrate that a voltage gated K(+) channel in the excitable tissue of plants has properties of a memristor. This study can be a starting point for understanding mechanisms of memory, learning, circadian rhythms, and biological clocks.


Assuntos
Aloe/fisiologia , Droseraceae/fisiologia , Eletricidade , Mimosa/fisiologia , Canais de Potássio de Abertura Dependente da Tensão da Membrana/fisiologia
4.
Plant Signal Behav ; 9(7): e29056, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25763487

RESUMO

A memristor is a resistor with memory, which is a non-linear passive two-terminal electrical element relating magnetic flux linkage and electrical charge. Here we found that memristors exist in vivo. The electrostimulation of the Aloe vera by bipolar sinusoidal or triangle periodic waves induce electrical responses with fingerprints of memristors. Uncouplers carbonylcyanide-3-chlorophenylhydrazone and carbonylcyanide-4-trifluoromethoxy-phenyl hydrazone decrease the amplitude of electrical responses at low and high frequencies of bipolar periodic sinusoidal or triangle electrostimulating waves. Memristive behavior of an electrical network in the Aloe vera is linked to the properties of voltage gated ion channels: the K(+) channel blocker TEACl reduces the electric response to a conventional resistor. Our results demonstrate that a voltage gated K(+) channel in the excitable tissue of plants has properties of a memristor. The discovery of memristors in plants creates a new direction in the modeling and understanding of electrical phenomena in plants.


Assuntos
Aloe/fisiologia , Eletricidade , Folhas de Planta/fisiologia , Canais de Potássio de Abertura Dependente da Tensão da Membrana/fisiologia , Impedância Elétrica , Canais de Potássio de Abertura Dependente da Tensão da Membrana/metabolismo
5.
Plant Signal Behav ; 9(8): e29204, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25763613

RESUMO

A memristor is a nonlinear element because its current-voltage characteristic is similar to that of a Lissajous pattern for nonlinear systems. We investigated the possible presence of memristors in the electrical circuitry of the Venus flytrap's upper and lower leaves. The electrostimulation of this plant by bipolar sinusoidal or triangle periodic waves induces electrical responses in the upper and lower leaves of the Venus flytrap with fingerprints of memristors. The analysis was based on cyclic voltammetric characteristics where the memristor, a resistor with memory, should manifest itself. Tetraethylammonium chloride, an inhibitor of voltage gated K(+) channels, or NPPB, a blocker of voltage gated Cl(-) and K(+) channels, transform a memristor to a resistor in plant tissue. Uncouplers carbonylcyanide-3-chlorophenylhydrazone (CCCP) and carbonylcyanide-4-trifluoromethoxy-phenyl hydrazone (FCCP) decrease the amplitude of electrical responses at low and high frequencies of bipolar periodic electrostimulating waves. Our results demonstrate that voltage gated K(+) channels in the Venus flytrap have properties of memristors of type 1 and type 2. The discovery of memristors in plants creates a new direction in the modeling and understanding of electrical phenomena in plants.


Assuntos
Droseraceae/fisiologia , Eletricidade , Ativação do Canal Iônico , Folhas de Planta/fisiologia , Canais de Potássio de Abertura Dependente da Tensão da Membrana/fisiologia , Eletrofisiologia , Bloqueadores dos Canais de Potássio/farmacologia , Canais de Potássio de Abertura Dependente da Tensão da Membrana/metabolismo , Ionóforos de Próton/farmacologia , Transdução de Sinais
6.
Plant Signal Behav ; 9(10): e982029, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25482796

RESUMO

The fourth basic circuit element, a memristor, is a resistor with memory that was postulated by Chua in 1971. Here we found that memristors exist in vivo. The electrostimulation of the Mimosa pudica by bipolar sinusoidal or triangle periodic waves induce electrical responses with fingerprints of memristors. Uncouplers carbonylcyanide-3-chlorophenylhydrazone and carbonylcyanide-4-trifluoromethoxy-phenyl hydrazone decrease the amplitude of electrical responses at low and high frequencies of bipolar sinusoidal or triangle periodic electrostimulating waves. Memristive behavior of an electrical network in the Mimosa pudica is linked to the properties of voltage gated ion channels: the channel blocker TEACl reduces the electric response to a conventional resistor. Our results demonstrate that a voltage gated K(+) channel in the excitable tissue of plants has properties of a memristor. The discovery of memristors in plants creates a new direction in the modeling and understanding of electrical phenomena in plants.


Assuntos
Eletricidade , Fenômenos Eletrofisiológicos , Mimosa/fisiologia , Carbonil Cianeto m-Clorofenil Hidrazona/farmacologia , Estimulação Elétrica , Fenômenos Eletrofisiológicos/efeitos dos fármacos , Mimosa/efeitos dos fármacos , Pulvínulo/efeitos dos fármacos , Pulvínulo/fisiologia
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