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1.
Angew Chem Int Ed Engl ; 63(8): e202315599, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38169100

RESUMO

Polypeptides, as natural polyelectrolytes, are assembled into tailored proteins to integrate chromophores and catalytic sites for photosynthesis. Mimicking nature to create the water-soluble nanoassemblies from synthetic polyelectrolytes and photocatalytic molecular species for artificial photosynthesis is still rare. Here, we report the enhancement of the full-spectrum solar-light-driven H2 production within a supramolecular system built by the co-assembly of anionic metalloporphyrins with cationic polyelectrolytes in water. This supramolecular photocatalytic system achieves a H2 production rate of 793 and 685 µmol h-1 g-1 over 24 h with a combination of Mg or Zn porphyrin as photosensitizers and Cu porphyrin as a catalyst, which is more than 23 times higher than that of free molecular controls. With a photosensitizer to catalyst ratio of 10000 : 1, the highest H2 production rate of >51,700 µmol h-1 g-1 with a turnover number (TON) of >1,290 per molecular catalyst was achieved over 24 h irradiation. The hierarchical self-assembly not only enhances photostability through forming ordered stackings of the metalloporphyrins but also facilitates both energy and electron transfer from antenna molecules to catalysts, and therefore promotes the photocatalysis. This study provides structural and mechanistic insights into the self-assembly enhanced photostability and catalytic performance of supramolecular photocatalytic systems.

2.
Opt Express ; 30(13): 23227-23237, 2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-36225008

RESUMO

A fiber optic accelerometer with a high sensitivity, low noise, and compact size is proposed for low-frequency acceleration sensing. The sensor is composed of a 20 mm diameter spherical outer frame and a three-dimensional spring-mass structure as the inertial sensing element. Three Fabry-Pérot interferometers (FPI) are formed between flat fiber facets and cubic mass surfaces to measure the FPI cavity length change caused by acceleration. The dynamic signal sensing of the designed accelerometer is performed, which shows a high acceleration sensitivity of 42.6 dB re rad/g with a working band of 1-80 Hz. An average minimum detectable acceleration of 4.5 µg/Hz1/2 can be obtained. The sensor features simple assembling, small size, light weight, and good consistency. Its transverse sensitivity is measured to be less than 3% (-30 dB) of the sensitive axis. The experimental result indicates that the proposed accelerometer has application potential in areas such as seismic wave detection and structural health monitoring.

3.
Opt Express ; 30(26): 47587-47597, 2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36558684

RESUMO

In this article, a fiber optic accelerometer based on a Fabry-Perot interferometer is presented and prepared by micromachining on a silicon substrate. The inertial sensing structure of the accelerometer is built by a center block mass and four folded springs with a high thickness-to-width ratio, providing an in-plane resonance vibration. The miniature-sized sensor has large flexibility in structural design and its acceleration response can be predicted by theoretical estimation and finite element simulation. Experimental results show that the proposed sensor's sensitivity is over 161 rad/g in frequency range of 1 to 63 Hz. It also achieved a low average noise level of 67.4 ng/Hz1/2 on the working band. The sensor's transverse crosstalk is less than 1.38%, proving its potential ability in low frequency vibration detection applications.

4.
Opt Express ; 30(6): 9307-9320, 2022 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-35299362

RESUMO

A miniaturized fiber optic hydrophone (FOH) based on a composite metal diaphragm with an air back cavity and a high finesse extrinsic Fabry-Perot interferometric (EFPI) scheme for low-frequency underwater acoustic sensing is proposed and experimentally demonstrated in this paper. A composite metal diaphragm is used to improve the stability of the hydrophone. A balance channel is used to equilibrate the hydrostatic pressure and maintain an air cavity, which improves the mechanical sensitivity. In addition, a white light interferometry (WLI) phase demodulation is used to demodulate the high finesse interferometer consisted of the fiber collimator end face and the diaphragm, which improves the phase sensitivity. Experimental results show that the enhanced phase sensitivity of the hydrophone is about -122.5 dB re 1 rad/µPa @ 200 Hz and the sensitivity fluctuation is below 2.5 dB between 3 Hz and 400 Hz, while the minimal detectable pressure (MDP) is 63.7 µPa/Hz1/2 @ 400 Hz. Due to its miniaturized structure and high sensitivity, the FOH may have an enormous potential in underwater target detection.

5.
Opt Lett ; 47(10): 2406-2409, 2022 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-35561362

RESUMO

In this Letter, we report a four-wavelength quadrature phase demodulation technique for extrinsic Fabry-Perot interferometric (EFPI) sensors and dynamic signals. Four interferometric signals are obtained from four different laser wavelengths. A wavelength interval of four wavelengths is chosen according to the free spectrum range (FSR) of EFPI sensors to generate two groups of anti-phase signals and two groups of orthogonal signals. The linear fitting (LF) method is applied to two groups of anti-phase signals to eliminate the dc component and ac amplitude to obtain two normalized orthogonal signals. The differential cross multiplication (DCM) method is then used to demodulate the phase signal from these two normalized orthogonal signals. The proposed LF and DCM (LF-DCM) based four-wavelength quadrature phase demodulation overcomes the drawback of the traditional ellipse fitting (EF) and DCM (EF-DCM) based dual-wavelength demodulation method that it is not suitable for weak signal demodulation since the ellipse degenerates into a straight line, which makes the EF algorithm invalid. Moreover, it also avoids the assumption that the dc component and ac amplitude of interferometric signals are identical, which is widely used in three-wavelength demodulation. An EFPI acoustic sensor is tested to prove the four-wavelength quadrature phase demodulation and experimental results show that the proposed phase demodulation method shows advantages of large dynamic range and wide frequency band. Linearity is as high as 0.9999 and a high signal-to-noise ratio (SNR) is observed from 1 Hz to 100 kHz.

6.
Sensors (Basel) ; 22(7)2022 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-35408103

RESUMO

A large-dynamic-range and high-stability phase demodulation technology for fiber-optic Michelson interferometric sensors is proposed. This technology utilizes two output signals from a 2 × 2 fiber-optic coupler, the interferometric phase difference of which is π. A linear-fitting trigonometric-identity-transformation differential cross-multiplication (LF-TIT-DCM) algorithm is used to interrogate the phase signal from the two output signals from the coupler. The interferometric phase differences from the two output signals from the 2 × 2 fiber-optic couplers with different coupling ratios are all equal to π, which ensures that the LF-TIT-DCM algorithm can be applied perfectly. A fiber-optic Michelson interferometric acoustic sensor is fabricated, and an acoustic signal testing system is built to prove the proposed phase demodulation technology. Experimental results show that excellent linearity is observed from 0.033 rad to 3.2 rad. Moreover, the influence of laser wavelength and optical power is researched, and variation below 0.47 dB is observed at different sound pressure levels (SPLs). Long-term stability over thirty minutes is tested, and fluctuation is less than 0.36 dB. The proposed phase demodulation technology obtains large dynamic range and high stability at rather low cost.

7.
Sensors (Basel) ; 22(21)2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36366158

RESUMO

In this paper, a novel inline optical fiber sensor for curvature and temperature measurement simultaneously has been proposed and demonstrated, which can measure two parameters with very little crosstalk. Two combinational mechanisms of anti-resonant reflecting optical waveguide and inline Mach-Zehnder interference structure are integrated into a 3 mm-long single hole twin suspended core fiber (SHTSCF). The 85 µm hole core gives periodic several dominant resonant wavelengths in the optical transmission spectrum, acting as the anti-resonant reflecting optical waveguide (ARROW). The modes in two suspended cores and the cladding form the comb pattern. Reliable sensor sensitivity can be obtained by effective experiments and demodulation. Through intensity demodulation of the selected dip of Gaussian fitting, the curvature sensitivity can be up to -7.23 dB/m-1. Through tracking the MZI dip for wavelength demodulation, the temperature sensitivity can be up to 28.8 pm/°C. The sensor is simple in structure, compact, and has good response, which can have a bright application in a complex environment.

8.
Sensors (Basel) ; 21(24)2021 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-34960351

RESUMO

A passive homodyne phase demodulation technique based on a linear-fitting trigonometric-identity-transformation differential cross-multiplication (LF-TIT-DCM) algorithm is proposed. This technique relies on two interferometric signals whose interferometric phase difference is odd times of π. It is able to demodulate phase signals with a large dynamic range and wide frequency band. An anti-phase dual wavelength demodulation system is built to prove the LF-TIT-DCM algorithm. Comparing the traditional quadrature dual wavelength demodulation system with an ellipse fitting DCM (EF-DCM) algorithm, the phase difference of two interferometric signals of the anti-phase dual wavelength demodulation system is set to be π instead of π/2. This technique overcomes the drawback of EF-DCM-that it is not able to demodulate small signals since the ellipse degenerates into a straight line and the ellipse fitting algorithm is invalidated. Experimental results show that the dynamic range of the proposed anti-phase dual wavelength demodulation system is much larger than that of the traditional quadrature dual wavelength demodulation system. Moreover, the proposed anti-phase dual wavelength demodulation system is hardly influenced by optical power, and the laser wavelength should be strictly limited to lower the reference error.

9.
Opt Express ; 28(17): 25238-25249, 2020 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-32907049

RESUMO

A Michelson interferometric fiber-optic acoustic sensor based on a large-area gold diaphragm is proposed in this paper. The Michelson interferometer (MI) based on 3×3 coupler is comprised of two beams that reflected from the gold diaphragm and a cleaved fiber end face. Thickness and diameter of the gold diaphragm are 300 nm and 2.5 mm, respectively. Based on the phase difference between each output port of the 3×3 fiber coupler, an ellipse fitting differential cross multiplication (EF-DCM) interrogation process is induced for phase demodulation, which can overcome the phase distortion caused by property degradation of 3×3 coupler. Experimental results show that the sensor has a phase sensitivity of about -130.6 dB re 1 rad/µPa@100 Hz. A flat response range between 0.8 to 250 Hz is realized with the sensitivity fluctuation below 0.7 dB. Besides, the signal-to-noise ratio (SNR) and minimal detectable pressure (MDP) of the sensor are 57.9 dB and 10.2 mPa/Hz1/2 at 5 Hz. The proposed sensor exhibits superiorities of compact size, high sensitivity, flat low-frequency response and ease of mass production, which gives the sensor great potential for low-frequency acoustic sensing and photo-acoustic spectroscopy.

10.
Opt Express ; 27(17): 24300-24310, 2019 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-31510321

RESUMO

In this work we demonstrate a low-frequency acoustic sensor structure based on extrinsic Fabry-Pérot interferometer (EFPI) cavity. The cavity is fabricated through micromachining techniques in a square silicon substrate with 4 mm side length and 400 µm thickness, which gives the sensor relative compact size. In the assembling process of the lead-in fiber, a D-shaped ceramic ferrule is designed to achieve the open cavity structure, which can balance the environmental pressure inside and outside the cavity and thus giving the sensor potentials of resisting strong pressure variations in some harsh application environments. Experimentally, sensor response to low-frequency acoustic waves from 0.1 Hz to 250 Hz is measured and demonstrated. A flat response region between 0.5 Hz to 250 Hz with sensitivity fluctuation of 0.8 dB is realized. Pressure resistant test of 25 MPa is also conducted on the sensor and exhibited to prove the function of the open cavity structure.

11.
Zhongguo Zhong Yao Za Zhi ; 44(10): 2084-2089, 2019 May.
Artigo em Zh | MEDLINE | ID: mdl-31355565

RESUMO

To reveal the transformation and attribution of drug properties in Galla Chinesis fermented Baiyaojian by studying the effect of Galla Chinesis and Baiyaojian on cold and heat syndrome rats. Euthyrox was used to induce the hyperthyrosis model,ice water stimulation was used to induce the cold syndrome model,and different concentrations of Galla Chinesis and Baiyaojian water decoction were administrated by gavage for 15 d continuously. Symptom indexes were evaluated,content of pyruvic acid( PA),ATPase activity in liver and contents of DA,T4,cAMP,5-HT,NE,17-OHCS,TRH and TSH in serum were assayed by enzyme linked immunosorbent assay and spectrophotometry. The rectal temperature,water consumption and body weight of heat syndrome rats in model group were increased,cAMP,NE,17-OHCS,TRH and PA were increased,TSH,Na-K ATPase and Ca-Mg ATPase were increased significantly( P<0. 01),while 5-HT was decreased,compared with those of the blank group( P< 0. 05),the contents of T4,DA,NE,TSH,TRH,cAMP and 17-OHCS were decreased significantly( P<0. 01),PA and Ca-Mg ATPase in WG and BG groups were decreased compared with those of the model group( P<0. 05),and the Galla Chinesis content of WG group was lower than that of BG group,while the contents of 5-HT in WG and BG groups were increased,and the Galla Chinesis content of WG group was higher than that of BG group,with no significant difference of viscera index between heat syndrome rats in blank group,model group and drug groups. The rectal temperature,water consumption and body weight of cold syndrome rats in model group were decreased,DA,T4,cAMP,NE,17-OHCS,TRH,TSH,PA,Na-K ATPase and Ca-Mg ATPase of rats in model group were decreased,whereas 5-HT was increased compared with those of the blank group( P<0. 05),the indexes of heart,lung and kidney were significantly higher than those in the blank group( P<0. 05). Both Galla Chinesis and Baiyaojian can significantly alleviate the symptoms of heat syndrome rats caused by levothyroxine sodium. Galla Chinesis has a better effect than Baiyaojian,but cannot alleviate the symptoms of cold syndrome caused by ice water stimulation,suggestting that the decoction of Galla Chinesis and Baiyaojian are both cold,but Galla Chinesis is colder than Baiyaojian. Cold property in Galla Chinesis fermented Baiyaojian can be relieved. In clinical application,the property of " slight cold" is more accurate than " neutral property" for Baiyaojian.


Assuntos
Resposta ao Choque Frio , Medicamentos de Ervas Chinesas/farmacologia , Resposta ao Choque Térmico , Animais , Temperatura Baixa , Coração , Temperatura Alta , Rim , Fígado , Pulmão , Medicina Tradicional Chinesa , Ratos
12.
Opt Express ; 26(16): 20758-20767, 2018 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-30119381

RESUMO

An ultra-wideband fiber optic acoustic sensor based on graphene diaphragm with a thickness of 10nm has been proposed and experimentally demonstrated. The two reflectors of the extrinsic Fabry-Perot interferometer is consist of fiber endface and graphene diaphragm, and the cavity is like a horn-shape. The radius of the effective area of the ultrathin graphene diaphragm is 1mm. Attributed to the strong van der Waals force between the diaphragm and the ceramic ferrule, the sensor head can be applied not only in the air but also underwater. Experimental results illustrate that ultra-wideband frequency response is from 5Hz to 0.8MHz, covering the range from infrasound to ultrasound. The noise-limited minimum detectable pressure level of 0.77Pa/Hz1/2@5Hz and 33.97µPa/Hz1/2@10kHz can be achieved, and the applied sound pressure is 114dB and 65.8dB, respectively. The fiber optic acoustic sensor may have a great potential in seismic wave monitoring, photoacoustic spectroscopy and photoacoustic imaging application due to its compact structure, simple manufacturing, and low cost.

13.
Opt Express ; 26(14): 18341-18350, 2018 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-30114015

RESUMO

In this paper, a high resolution and large dynamic range fiber optic temperature sensor without measurement crosstalk has been proposed. Two combinational mechanisms of anti-resonant reflecting optical waveguide and inline Mach-Zehnder interference structure are integrated in single hole twin eccentric cores fiber. The dual-effect composite spectrum is consist of several dominant resonant wavelengths and comb pattern, which are corresponding to the two above-mentioned mechanisms. Gauss fit and fast Fourier transform filtering are used for extracting the resonant wavelengths and comb spectrum, respectively. Accordingly, the temperature sensitivity of 42.18pm/°C and 2.057nm/°C are achieved by tracking the coherent decrease point. The lower sensitivity can guarantee a large dynamic range, while the higher one will contribute to the enhanced resolution. Therefore, the temperature monitoring is the combination of large dynamic range and enhanced resolution. Moreover, the size of the ultracompact sensor is only 950µm, which has a great potential for engineering applications.

14.
Opt Express ; 25(4): 4429-4437, 2017 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-28241645

RESUMO

In this article, we propose an interrogation method of fiber acoustic sensor to recover the time-domain signal from the sensor spectrum. The optical spectrum of the sensor will show a ripple waveform when responding to acoustic signal due to the scanning process in a certain wavelength range. The reason behind this phenomenon is the dynamic variation of the sensor spectrum while the intensity of different wavelength is acquired at different time in a scanning period. The frequency components can be extracted from the ripple spectrum assisted by the wavelength scanning speed. The signal is able to be recovered by differential between the ripple spectrum and its self-fitted curve. The differential process can eliminate the interference caused by environmental perturbations such as temperature or refractive index (RI), etc. The proposed method is appropriate for fiber acoustic sensors based on gratings or interferometers. A long period grating (LPG) is adopted as an acoustic sensor head to prove the feasibility of the interrogation method in experiment. The ability to compensate the environmental fluctuations is also demonstrated.

15.
Opt Express ; 25(18): 21094-21106, 2017 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-29041517

RESUMO

A demodulation method for interferometric fiber sensors (IFSs) is proposed in this article. The phase variation induced by the measurands can be estimated by calculating the Fourier phase at the intrinsic spatial frequencies of the fiber sensor. Theoretical analysis of the demodulation method is discussed in detail. Numerical simulations are put forward to demonstrate the consistency of the demodulation results under different wavelength sampling interval and noise level, showing a better stability compared with the conventional peak wavelength tracking technique. The proposed method is also experimentally demonstrated by an inline multimode interferometer based on a single-mode fiber (SMF) offset-splicing structure. Experimental results indicate that the phase response of different cladding modes can be analyzed simultaneously. Simultaneous measurement of strain and temperature is realized in our confirmatory experiment by analyzing the phase sensitivities of two selected cladding modes.

16.
Opt Express ; 25(22): 26898-26909, 2017 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-29092173

RESUMO

In this paper, a novel sensitivity amplification method for fiber-optic in-line Mach-Zehnder interferometer (MZI) sensors has been proposed and demonstrated. The sensitivity magnification is achieved through a modified Vernier-effect. Two cascaded in-line MZIs based on offset splicing of single mode fiber (SMF) have been used to verify the effect of sensitivity amplification. Vernier-effect is generated due to the small free spectral range (FSR) difference between the cascaded in-line MZIs. Frequency component corresponding to the envelope of the superimposed spectrum is extracted to take Inverse Fast Fourier Transform (IFFT). Thus we can obtain the envelope precisely from the messy superimposed spectrum. Experimental results show that a maximum sensitivity amplification factor of nearly 9 is realized. The proposed sensitivity amplification method is universal for the vast majority of in-line MZIs.

17.
Opt Express ; 25(11): 12372-12380, 2017 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-28786593

RESUMO

A novel fiber curvature sensor without temperature cross interference based on a single hole twin eccentric core fiber has been proposed. Anti-resonant mechanism combined with inline Mach-Zehnder interference (MZI) structure are applied to the measurands detection. The spectrum is composed of a comb spectrum caused by the inline MZI and several dominant resonant wavelengths induced by anti-resonant effect. The curvature sensitivity of -1.54dB/m-1 can be achieved by intensity demodulation of the selected dip of Gaussian fitting. Similarly, the temperature sensitivity of 70.71pm/°C and 34.17pm/°C are respectively achieved by tracking coherent decrease point obtained by the FFT band pass filter method and Gaussian fit dip. Consequently, a relatively higher resolution of temperature measurement can be realized by the two methods mentioned above. The proposed sensor has a great potential for structural health monitoring, such as buildings, towers, bridges, and many other infrastructures due to its compact structure, easy fabrication and without cross impacts.

18.
Int J Clin Pharmacol Ther ; 55(10): 789-797, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28766499

RESUMO

Platelet activation and aggregation play an important role in the pathological and physiological processes of recurrent ischemic vascular events in stroke patients. The purpose of this study is to determine the association between platelet function measured in the acute period and recurrent ischemic vascular events in patients with transient ischemic attack (TIA) or minor stroke. A total of 417 patients who were within the 24-hour period of clopidogrel-aspirin therapy after onset of a minor stroke or high-risk transient ischemic attack according to the Clopidogrel in High-risk patients with Acute Nondisabling Cerebrovascular Events (CHANCE) trial were included in this study. The platelet aggregation ratio was detected using a method of continuous platelet counting; patients underwent CYP2C19 genotyping, and the baseline data were recorded. The patients underwent a 6-month follow-up period during which the recurrent ischemic vascular events were observed. Logistic regression analysis was performed to obtain the risk factors for recurrent ischemic vascular events. The number of patients with recurrent ischemic events who had an arachidonic acid-induced maximum platelet aggregation ratio (MAR-AA) (aspirin 100 mg) (31.85 ± 12.86 vs. 26.71 ± 12.44, p = 0.007) and adenosine diphosphate-induced maximum platelet aggregation ratio (MAR-ADP) after the administration of 75 mg clopidogrel for 12 ± 2 days (65.82 ± 10.72 vs. 53.10 ± 12.98, p < 0.001) was significantly higher compared with the no ischemic vascular event group. Multivariate logistic regression analyses showed that being a carrier of the CYP2C19 loss-of-function (LOF) allele (OR = 2.308, 95% CI: 1.087 ~ 4.901, p = 0.029) as well as the MAR-AA (aspirin 100 mg) (OR = 1.028, 95% CI: 1.006  ~  1.052, p = 0.014) and MAR-ADP after the administration of 75 mg clopidogrel (OR = 1.067, 95% CI: 1.037 ~ 1.095, p < 0.001) were risk factors for ischemic vascular events. The MAR-ADP after the administration of 75 mg clopidogrel was significantly higher in patients who were carriers of the CYP2C19 (LOF) allele compared with non-carriers (57.53 ± 13.32 vs. 50.86 ± 12.55, p < 0.001), and no significant differences between the CYP2C19 LOF allele carriers and non-carriers in the MAR-ADP were detected after the administration of 300 mg clopidogrel (37.18 ± 11.36 vs. 35.86 ± 12.49, p = 0.264). Being a carrier of the CYP2C19 LOF allele has a significant influence on clopidogrel response. Platelet function is closely related to recurrent ischemic vascular events in acute minor stroke or TIA patients.
.


Assuntos
Plaquetas/fisiologia , Ataque Isquêmico Transitório/fisiopatologia , Acidente Vascular Cerebral/fisiopatologia , Alelos , Aspirina/uso terapêutico , Testes de Coagulação Sanguínea/métodos , Plaquetas/efeitos dos fármacos , Clopidogrel , Citocromo P-450 CYP2C19/genética , Feminino , Genótipo , Humanos , Ataque Isquêmico Transitório/tratamento farmacológico , Ataque Isquêmico Transitório/genética , Masculino , Pessoa de Meia-Idade , Ativação Plaquetária/efeitos dos fármacos , Ativação Plaquetária/genética , Ativação Plaquetária/fisiologia , Agregação Plaquetária/efeitos dos fármacos , Agregação Plaquetária/genética , Agregação Plaquetária/fisiologia , Inibidores da Agregação Plaquetária/uso terapêutico , Testes de Função Plaquetária/métodos , Recidiva , Acidente Vascular Cerebral/genética , Ticlopidina/análogos & derivados , Ticlopidina/uso terapêutico , Resultado do Tratamento
19.
Eur Neurol ; 74(1-2): 86-91, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26288230

RESUMO

BACKGROUND: The purpose of this study was to observe the incidence of falls in Parkinson's disease (PD) patients with different cognitive levels and to investigate the effect of the cholinesterase inhibitor Rivastigmine on cognitive dysfunction and falling in PD patients. SUBJECTS AND METHODS: Data from 176 PD patients participating in the collaborative PD study between June 2010 and June 2014 were collected; the Chinese edition of the Montreal Cognitive Assessment (MoCA) score was used to evaluate the cognitive function of patients, and falls were recorded. PD patients with cognitive dysfunction were randomly administered either a placebo or Rivastigmine. The cognitive function changes and difference in fall incidence were compared between the 2 groups. RESULTS: The average number of falls per person in PD patients without cognitive impairment dysfunction was significantly lower than that in patients in the PD mild cognitive impairment (PD-MCI) group and that in the PD dementia (PDD) group (p < 0.01, p < 0.001, respectively), and the incidence of falls was significantly lower than that in patients in the PD-MCI and PDD groups (p < 0.01, p < 0.01, respectively). Compared to the PD-MCI group, the incidence of falls of patients in the PDD group (OR 2.45, 95% CI 0.97-6.20, p < 0.01) and the number of falls per person were significantly increased (p < 0.01). After taking the placebo or Rivastigmine for 12 months, the MoCA scores of patients in the Rivastigmine treatment group were significantly higher than those of the control group (p = 0.002). The number of falls per person and the incidence of falls of patients in Rivastigmine treatment group were significantly lower than those in the placebo group (p < 0.01). CONCLUSION: This study suggests that the degree of cognitive impairment is closely associated with the incidence of falls, and the cholinesterase inhibitor Rivastigmine can delay the deterioration of cognitive function and lower the incidence of falls in PD patients.


Assuntos
Acidentes por Quedas/prevenção & controle , Inibidores da Colinesterase/uso terapêutico , Doença de Parkinson/tratamento farmacológico , Rivastigmina/uso terapêutico , Acidentes por Quedas/estatística & dados numéricos , Idoso , Disfunção Cognitiva/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/complicações
20.
Eur Neurol ; 73(3-4): 205-211, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25792086

RESUMO

BACKGROUND: To investigate the effect of creatine and coenzyme Q10 (CoQ10) combination therapy on mild cognitive impairment (MCI) in Parkinson's disease (PD; PD-MCI) and its influences on plasma phospholipid (PL) levels in PD-MCI. METHODS: The demographic data of 75 PD-MCI patients who enrolled in this collaborative PD study were collected. These patients were evaluated using the Unified Parkinson's Disease Rating Scale (UPDRS) III and the Montreal Cognitive Assessment (MoCA). These 75 PD-MCI patients were randomly treated with creatine monohydrate 5 g b.i.d. and CoQ10 100 mg t.i.d. orally or placebo. MoCA evaluation and PL level measurements were performed after 12 and 18 months of treatment. RESULTS: After 12 and 18 months of treatment, the differences in the MoCA scores of the combination therapy and control groups were statistically significant (p < 0.05 at 12 months and p < 0.01 at 18 months), and the plasma PL levels of the combination therapy group were significantly lower than those of the control group (p < 0.01 at 12 months and p < 0.001 at 18 months). CONCLUSIONS: Combination therapy with creatine and CoQ10 could delay the decline of cognitive function in PD-MCI patients and could lower their plasma PL levels; therefore, this combination therapy may have a neuroprotective function.


Assuntos
Cognição/efeitos dos fármacos , Disfunção Cognitiva/tratamento farmacológico , Creatina/administração & dosagem , Doença de Parkinson/complicações , Ubiquinona/análogos & derivados , Idoso , Disfunção Cognitiva/etiologia , Quimioterapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/psicologia , Ubiquinona/administração & dosagem
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