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1.
Front Physiol ; 13: 938486, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36035484

RESUMO

Objective : The purpose of this study was to explore the effects of renal denervation (RDN) on cardiac function and malignant arrhythmia in patients with reduced left ventricular ejection fraction (HFrEF) and narrow QRS treated with an implantable cardioverter defibrillator (ICD). Methods: A total of 20 eligible HFrEF patients [left ventricular ejection fraction (LVEF) <40%] and narrow QRS complexes (QRS duration <120 ms) were randomized into either the ICD plus RDN group or the ICD only group during 17 April 2014 to 22 November 2016. Clinical data, including clinical characteristics, blood biochemistry, B-type natriuretic peptide, echocardiographic indexes, 6-min walk distance (6MWD), New York Heart Association (NYHA) classification, and count of ICD discharge events before and after the operation were analyzed. Patients were followed up for up to 3 years post ICD or ICD plus RDN. Results: Baseline clinical data were comparable between the two groups. Higher LVEF (%) (mixed model repeated measure, p = 0.0306) (39.50% ± 9.63% vs. 31.20% ± 4.52% at 1 year; 41.57% ± 9.62% vs. 31.40% ± 8.14% at 3 years), systolic blood pressure (p = 0.0356), and longer 6MWD (p < 0.0001) as well as reduction of NYHA classification (p < 0.0001) were evidenced in the ICD plus RDN group compared to ICD only group during follow-up. Patients in the ICD plus RDN group experienced fewer ICD discharge events (2 vs. 40) and decreased diuretic use; rehospitalization rate (30% vs. 100%, p = 0.0031) and cardiogenic mortality rate (0% vs. 50%, p = 0.0325) were also significantly lower in the ICD plus RDN group than in the ICD only group during follow-up. Conclusion: ICD implantation plus RDN could significantly improve cardiac function and cardiac outcome as well as increase exercise capacity compared to ICD only for HFrEF patients with narrow QRS complexes.

2.
Curr Alzheimer Res ; 18(14): 1077-1086, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34911423

RESUMO

BACKGROUND: Alzheimer's disease (AD) is a chronic neurodegenerative disease that has been characterized by progressive development of long onset early disease with complicated etiology and may cause memory loss, cognitive impairment, and behavioral changes. Physical exercise may play a preventive role in AD. In the present study, we investigated the impact of longer-term physical exercise on the finger tapping of AD patients by comparing the finger tapping of AD patients and healthy controls. METHODS: In this study, 140 subjects aged ≥ 60 years were enrolled. Group A consisted of 70 subjects (27 males and 43 females) without exercise habits who were selected from Yangpu District (Shanghai, China). Group B consisted of 70 subjects (27 males and 43 females) who were selected from Minxing District (Shanghai, China). All the subjects were right-handed as well. The subjects' data, including subjects' age, weight, height, Montreal Cognitive Assessment (MoCA), Mini-Mental State Examination (MMSE), and finger tapping frequency, were measured. RESULTS: The subjects were matched in age, weight, and height. The AD subjects' MoCA and MMSE scores were noticeably lower than healthy subjects' scores (P<0.001); besides, AD patients with exercise had significantly lower MoCA and MMSE scores than healthy controls with exercise (P<0.001). The finger tapping of AD subjects' left hands was significantly lower than that of healthy subjects without AD (P<0.01), and AD subjects with exercise tapped significantly slower with their left hand than healthy subjects with exercise (P<0.01). Meanwhile, AD subjects with exercise tapped significantly faster with the left hand than AD subjects (P<0.05). The right hands of AD subjects tapped remarkably less than healthy subjects (P<0.01) with or without exercise. Meanwhile, subjects with exercise tapped significantly faster with their right hand than healthy subjects (P<0.05), and AD subjects with exercise tapped significantly faster with their right hand than AD subjects (P<0.05). CONCLUSION: Long-term physical exercises can improve finger tapping frequency, especially in patients with AD. Finger tapping frequency may be used as an index to monitor the cognitive decline in ageing AD patients.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Doenças Neurodegenerativas , Doença de Alzheimer/diagnóstico , China , Disfunção Cognitiva/diagnóstico , Exercício Físico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos
3.
Nanomaterials (Basel) ; 11(6)2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-34207676

RESUMO

High-temperature-resistant polymeric adhesives with high servicing temperatures and high adhesion strengths are highly desired in aerospace, aviation, microelectronic and other high-tech areas. The currently used high-temperature resistant polymeric adhesives, such as polyamic acid (PAA), are usually made from the high contents of solvents in the composition, which might cause adhesion failure due to the undesirable voids caused by the evaporation of the solvents. In the current work, electrospun preimidized polyimide (PI) nano-fibrous membranes (NFMs) were proposed to be used as solvent-free or solvent-less adhesives for stainless steel adhesion. In order to enhance the adhesion reliability of the PI NFMs, thermally crosslinkable phenylethynyl end-cappers were incorporated into the PIs derived from 3,3',4,4'-oxydiphthalic anhydride (ODPA) and 3,3-bis[4-(4-aminophenoxy)phenyl]phthalide (BAPPT). The derived phenylethynyl-terminated PETI-10K and PETI-20K with the controlled molecular weights of 10,000 g mol-1 and 20,000 g mol-1, respectively, showed good solubility in polar aprotic solvents, such as N-methyl-2-pyrrolidinone (NMP) and N,N-dimethylacetamide (DMAc). The PI NFMs were successfully fabricated by electrospinning with the PETI/DMAc solutions. The ultrafine PETI NFMs showed the average fiber diameters (dav) of 627 nm for PETI-10K 695 nm for PETI-20K, respectively. The PETI NFMs showed good thermal resistance, which is reflected in the glass transition temperatures (Tgs) above 270 °C. The PETI NFMs exhibited excellent thermoplasticity at elevated temperatures. The stainless steel adherends were successfully adhered using the PETI NFMs as the adhesives. The PI NFMs provided good adhesion to the stainless steels with the single lap shear strengths (LSS) higher than 20.0 MPa either at room temperature (25 °C) or at an elevated temperature (200 °C).

4.
Nanomaterials (Basel) ; 11(2)2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33669852

RESUMO

The rapid development of advanced high-frequency mobile communication techniques has advanced urgent requirements for polymer materials with high-temperature resistance and good dielectric properties, including low dielectric constants (low-Dk) and low dielectric dissipation factors (low-Df). The relatively poor dielectric properties of common polymer candidates, such as standard polyimides (PIs) greatly limited their application in high-frequency areas. In the current work, benzoxazole units were successfully incorporated into the molecular structures of the fluoro-containing PIs to afford the poly(imide-benzoxazole) (PIBO) nano-fibrous membranes (NFMs) via electrospinning fabrication. First, the PI NFMs were prepared by the electrospinning procedure from organo-soluble PI resins derived from 2,2'-bis(3,4-dicarboxy-phenyl)hexafluoropropane dianhydride (6FDA) and aromatic diamines containing ortho-hydroxy-substituted benzamide units, including 2,2-bis[3-(4-aminobenzamide)-4-hydroxylphenyl]hexafluoropropane (p6FAHP) and 2,2-bis[3-(3-aminobenzamide)-4-hydroxyphenyl]hexafluoropropane (m6FAHP). Then, the PI NFMs were thermally dehydrated at 350 °C in nitrogen to afford the PIBO NFMs. The average fiber diameters (dav) for the PIBO NFMs were 1225 nm for PIBO-1 derived from PI-1 (6FDA-p6FAHP) precursor and 816 nm for PIBO-2 derived from PI-2 (6FDA-m6FAHP). The derived PIBO NFMs showed good thermal stability with the glass transition temperatures (Tgs) over 310 °C and the 5% weight loss temperatures (T5%) higher than 500 °C in nitrogen. The PIBO NFMs showed low dielectric features with the Dk value of 1.64 for PIBO-1 and 1.82 for PIBO-2 at the frequency of 1 MHz, respectively. The Df values were in the range of 0.010~0.018 for the PIBO NFMs.

5.
Ying Yong Sheng Tai Xue Bao ; 28(3): 935-940, 2017 Mar 18.
Artigo em Chinês | MEDLINE | ID: mdl-29741022

RESUMO

Assara inouei Yanmanaka is an important pest of pomegranate fruits in Yunnan Province. To examine the effects of different pomegranate varieties on the development and reproduction of A. inouei, the biological characteristics, such as the developmental duration, the survival rate and reproduction of this pest feeding on five pomegranate varieties including Tianlvzi, Houpitianshazi, Tianguangyan, Suanlvzi and Suanshazi were observed respectively, and the life table parameters were established under the laboratory conditions of (25±1) ℃, RH (70±10)% and a photoperiod of 15 L:9 D. The results showed that there were no significant differences in the egg stage, larval stage, pupal stage, the longevity of male adults, generation duration form egg to adult and egg hatch rate among the five varieties. There were significant differences in the pre-pupal stage, the longevity of female adults, larval survival, pupation, eclosion and total survival rates, the number of eggs laid per female as well as male and female pupal mass among the five varieties, and all of which except the larval survival were higher on Suanlvzi, followed by Houpitianshazi, but there was no significant difference between these two varieties. The results of life table showed the net reproduction rate, the intrinsic rate of increase and finite rate of increase of the Suanlvzi population were the highest. There were no significant differences in the mean generation time among the five varieties, but significant difference was observed in the population doubling time, which was the shortest on Suanlvzi population. The development and reproduction of A. inouei were better on the Suanlvzi and Houpitianshazi among the five varieties.


Assuntos
Lepidópteros , Lythraceae , Animais , China , Feminino , Fertilidade , Larva , Masculino , Pupa , Reprodução
6.
Biomed Environ Sci ; 27(6): 471-4, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24961858

RESUMO

To establish an analytical method for determination of four bisphenols (BPA, BPB, BPF, and BPS) and two alkylphenols (4-n-OP, 4-n-NP) in water by ultra performance liquid chromatography- tandem mass spectrometry (UPLC/MS/MS). The water samples were extracted and condensed with solid-phase extraction (SPE) using C18 cartridges and eluted by acetonitrile. Separation was carried out with Acquity BEH C8 column and detection were performed by UPLC/MS/MS. Quantification was calculated by using the internal standard BPA-d16 and 4-n-NP-d8. The linear correlation coefficients of these compounds in the range of 1.0-100.0 µg/L were all over 0.999. The minimum detectable concentrations were 0.75-1.0 ng/L, and the recoveries ranged from 87.0% to 106.9%. Relative standard deviations (RSDs) were between 1.26% and 3.67%. Applying this method to detect the source water of Chaohu Lake and drinking water of Hefei, six target compounds were detected in different levels. This method is simple with high sensitivity and selectivity, could be suitable for the determination of these compounds in source and drinking water.


Assuntos
Disruptores Endócrinos/análise , Fenóis/análise , Poluentes Químicos da Água/análise , Cromatografia Líquida , Extração em Fase Sólida , Espectrometria de Massas em Tandem
7.
Biopolymers ; 97(10): 818-24, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22806501

RESUMO

Anticoagulation factor II (ACF II), a coagulation factor X- binding protein from the venom of Agkistrodon acutus has both anticoagulant and hypotensive activities. Previous studies show that ACF II binds specifically with activated factor X (FXa) in a Ca(2+) -dependent manner and inhibits intrinsic coagulation pathway. In this study, the inhibition of extrinsic coagulation pathway by ACF II was measured in vivo by prothrombin time assay and the binding of ACF II to factor IX (FIX) was investigated by native polyacrylamide gel electrophoresis and surface plasmon resonance (SPR). The results indicate that ACF II also inhibits extrinsic coagulation pathway, but does not inhibit thrombin activity. ACF II also binds with FIX with high binding affinity in a Ca(2+) -dependent manner and their maximal binding occurs at about 0.1 mM Ca(2+) . ACF II has similar binding affinity to FIX and FX as determined by SPR. Ca(2+) has a slight effect on the secondary structure of FIX as determined by circular dichroism spectroscopy. Ca(2+) ions are required to maintain in vivo function of FIX Gla domain for its recognition of ACF II. However, Ca(2+) at high concentrations (>0.1 mM) inhibits the binding of ACF II to FIX. Ca(2+) functions as a switch for the binding between ACF II and FIX. ACF II extends activated partial thromboplastin time more strongly than prothrombin time, suggesting that the binding of ACF II with FIX may play a dominant role in the anticoagulation of ACF II in vivo.


Assuntos
Agkistrodon , Cálcio/química , Venenos de Crotalídeos/química , Fator IX/química , Animais , Coagulação Sanguínea/efeitos dos fármacos , Dicroísmo Circular , Venenos de Crotalídeos/farmacologia , Eletroforese em Gel de Poliacrilamida , Ratos , Ressonância de Plasmônio de Superfície
8.
Biopolymers ; 93(2): 141-9, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19780128

RESUMO

AA-NADase from Agkistrodon acutus venom is a unique multicatalytic enzyme with both NADase and AT(D)Pase activities. Among all identified NADases, only AA-NADase contains Cu(II) and has disulfide-bond linkages between two peptide chains. The effects of the reduction of the disulfide-bonds and Cu(II) in AA-NADase by small-molecule reductants on its NADase and ADPase activities have been investigated by polyacrylamide gel electrophoresis, high performance liquid chromatography, electron paramagnetic resonance spectroscopy and isothermal titration calorimetry. The results show that AA-NADase has six disulfide-bonds and fifteen free cysteine residues. L-ascorbate inhibits AA-NADase on both NADase and ADPase activities through the reduction of Cu(II) in AA-NADase to Cu(I), while other reductants, dithiothreitol, glutathione and tris(2-carboxyethyl)phosphine inhibit both NADase and ADPase activities through the reduction of Cu(II) to Cu(I) and the cleavage of disulfide-bonds in AA-NADase. Apo-AA-NADase can recover its NADase and ADPase activities in the presence of 1 mM Zn(II). However, apo-AA-NADase does not recover any NADase or ADPase activity in the presence of 1 mM Zn(II) and 2 mM TCEP. The multicatalytic activity relies on both disulfide-bonds and Cu(II), while Cu(I) can not activate the enzyme activities. AA-NADase is probably only active as a dimer. The inhibition curves for both ADPase and NADase activities by each reductant share a similar trend, suggesting both ADPase and NADase activities probably occur at the same site. In addition, we also find that glutathione and L-ascorbate are endogenous inhibitors to the multicatalytic activity of AA-NADase.


Assuntos
Venenos de Crotalídeos/antagonistas & inibidores , Venenos de Crotalídeos/enzimologia , NAD+ Nucleosidase/antagonistas & inibidores , NAD+ Nucleosidase/química , Animais , Cobre/química , Cisteína/química , Dissulfetos/química , Ditiotreitol/farmacologia , Glutationa/farmacologia , Oxirredução , Fosfinas/farmacologia
9.
Neurosci Res ; 38(2): 183-91, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11000445

RESUMO

Peripheral nerve injury results in sprouting of sympathetic and sensory nerve terminals around large diameter neurons in the dorsal root ganglia (DRG), but the underlying mechanism is not clear. Current study sought to examine changes of the nerve growth factor (NGF) receptor TrkA in DRG and spinal cord after a spinal nerve transection by an immunohistochemical technique and to investigate effects of NGF on the expression of TrkA protein in the same animal model. In the control rat, TrkA immunoreactivity was localized to about 55 +/ -1% of total neurons in DRG and to laminae I and II of the spinal cord. The percentage of TrkA immunoreactive neurons in DRG and TrkA staining intensity of spinal cord were reduced 1 week after the nerve lesion. The changes became maximal 2 weeks, but recovered partially 4 weeks after the lesion. The size of TrkA immunoreactive neurons dramatically shifted to smaller sizes, becoming more remarkable 4 weeks after the lesion. In the contralateral DRG, the percentage of TrkA immunoreactive neurons also decreased significantly. Exogenous NGF delivered to DRG for 2 weeks partially reversed the reduction of TrkA expression as well as atrophy of TrkA immunoreactive neurons. No TrkA immunoreactive basket was found around neuronal somata. Our data show that unilateral peripheral nerve injury results in dynamic downregulation of TrkA in sensory neurons in bilateral DRG and spinal cord, and that TrkA expression in sensory neurons is partially regulated by target-derived NGF.


Assuntos
Fator de Crescimento Neural/farmacologia , Neurônios Aferentes/metabolismo , Receptor trkA/metabolismo , Nervos Espinhais/fisiologia , Animais , Denervação , Regulação para Baixo , Gânglios Espinais/efeitos dos fármacos , Gânglios Espinais/metabolismo , Gânglios Espinais/patologia , Imuno-Histoquímica , Região Lombossacral , Masculino , Neurônios Aferentes/patologia , Células do Corno Posterior/metabolismo , Ratos , Ratos Sprague-Dawley , Nervos Espinhais/patologia
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