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1.
Neural Regen Res ; 17(3): 682-689, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34380910

RESUMO

SNCA, GBA, and VPS35 are three common genes associated with Parkinson's disease. Previous studies have shown that these three genes may be associated with Alzheimer's disease (AD). However, it is unclear whether these genes increase the risk of AD in Chinese populations. In this study, we used a targeted gene sequencing panel to screen all the exon regions and the nearby sequences of GBA, SNCA, and VPS35 in a cohort including 721 AD patients and 365 healthy controls from China. The results revealed that neither common variants nor rare variants of these three genes were associated with AD in a Chinese population. These findings suggest that the mutations in GBA, SNCA, and VPS35 are not likely to play an important role in the genetic susceptibility to AD in Chinese populations. The study was approved by the Ethics Committee of Xiangya Hospital, Central South University, China on March 9, 2016 (approval No. 201603198).

2.
Aging (Albany NY) ; 13(8): 11352-11362, 2021 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-33833133

RESUMO

BACKGROUND: Three polymorphisms in the Methylenetetrahydrofolate reductase (MTHFR) gene (C677T, A1298C, and A1793G) were reported associated with AD. However, their genotype distributions and associations with age at onset (AAO), homocysteine, and white matter lesions (WML) were unclear in the Chinese AD population. METHOD: We determined the presence of C677T, A1298C, and A1793G polymorphisms in the MTHFR gene using Sanger sequencing in a Chinese cohort comprising 721 AD patients (318 early-onset AD patients (EOAD) and 403 late-onset AD patients (LOAD)) and 365 elderly controls. Additionally, the homocysteine level and WML were evaluated in 121 AD patients. RESULTS: The frequency of allele T of C677T polymorphism was significantly higher in AD patients than in controls (P = 0.040), while no statistical difference was observed in A1298C and A1793G (P > 0.05). Besides, genotype distributions of C677T and A1298C polymorphisms statistically varied between AD patients and controls (P = 0.021, P = 0.012). Moreover, the AAO was significantly lower in CT/TT (C677T) genotypes carriers (P = 0.042) and higher in AC/CC (A1298C) and AG/GG (A1793G) genotypes carriers (P = 0.034, P = 0.009) in patients with LOAD. We also found that patients with CT/TT (C677T) genotypes were prone to present an increased homocysteine level (P = 0.036) and higher Fazekas score (P = 0.024). In comparison, patients with AG/GG genotypes (A1793G) had a significantly lower Fazekas score (P = 0.013). CONCLUSIONS: The genotype distributions of C677T and A1298C polymorphisms are associated with AD in the Chinese population. Moreover, AD patients with C677T polymorphism are prone to present an earlier onset, higher homocysteine level, and more severe WML.


Assuntos
Doença de Alzheimer/genética , Predisposição Genética para Doença , Homocisteína/sangue , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Substância Branca/patologia , Idade de Início , Idoso , Alelos , Doença de Alzheimer/sangue , Doença de Alzheimer/epidemiologia , Doença de Alzheimer/patologia , Apolipoproteínas E/genética , Grupo com Ancestrais do Continente Asiático/genética , Estudos de Casos e Controles , China/epidemiologia , Feminino , Homocisteína/metabolismo , Humanos , Masculino , Metilenotetra-Hidrofolato Redutase (NADPH2)/metabolismo , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único
3.
J Parkinsons Dis ; 11(1): 93-105, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33104043

RESUMO

Progressive supranuclear palsy (PSP) is an atypical parkinsonism with prominent 4R-tau neuropathology, and the classical clinical phenotype is characterized by vertical supranuclear gaze palsy, unprovoked falls, akinetic-rigid syndrome and cognitive decline. Though PSP is generally regarded as sporadic, there is increasing evidence suggesting that a series of common and rare genetic variants impact on sporadic and familial forms of PSP. To date, more than 10 genes have been reported to show a potential association with PSP. Among these genes, the microtubule-associated protein tau (MAPT) is the risk locus with the strongest effect size on sporadic PSP in the case-control genome-wide association studies (GWAS). Additionally, MAPT mutations are the most common cause of familial PSP while the leucine-rich repeat kinase 2 (LRRK2) is a rare monogenic cause of PSP, and several other gene mutations may mimic the PSP phenotype, like the dynactin subunit 1 (DCTN1). In total, 15 MAPT mutations have been identified in cases with PSP, and the mean age at onset is much earlier than in cases carrying LRRK2 or DCTN1 mutations. GWAS have further identified several risk loci of PSP, proposing molecular pathways related to PSP. The present review focused on genetic studies on PSP and summarized genetic factors of PSP, which may help to elucidate the underlying pathogenesis and provide new perspectives for therapeutic strategies.

4.
BMC Med Genet ; 21(1): 235, 2020 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-33243190

RESUMO

BACKGROUND: Cerebral folate deficiency (CFD) is a neurological disease, hallmarked by remarkable low concentrations of 5-methyltetrahydrofolic acid (5-MTHF) in cerebrospinal fluid (CSF). The primary causes of CFD include the presence of folate receptor (FR) autoantibodies, defects of FR encoding gene FOLR1, mitochondrial diseases and congenital abnormalities in folate metabolism. CASE PRESENTATION: Here we first present a Chinese male CFD patient whose seizure onset at 2 years old with convulsive status epilepticus. Magnetic Resonance Imaging (MRI) revealed the development of encephalomalacia, laminar necrosis in multiple lobes of the brain and cerebellar atrophy. Whole Exome Sequencing (WES) uncovered a homozygous missense variant of c.524G > T (p.C175F) in FOLR1 gene. Further laboratory tests demonstrated the extremely low level of 5-MTHF in the CSF from this patient, which was attributed to cerebral folate transport deficiency. Following the intravenous and oral treatment of calcium folinate, the concentrations of 5-MTHF in CSF were recovered to the normal range and seizure symptoms were relieved as well. CONCLUSIONS: One novel variation of FOLR1 was firstly identified from a Chinese male patient with tonic-clonic seizures, developmental delay, and ataxia. The WES and laboratory results elucidated the etiology of the symptoms. Clinical outcomes were improved by early diagnosis and proper treatment.


Assuntos
Encefalomalacia/genética , Receptor 1 de Folato/genética , Deficiência de Ácido Fólico/genética , Convulsões/genética , Estado Epiléptico/genética , Idade de Início , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Criança , Encefalomalacia/líquido cefalorraquidiano , Encefalomalacia/diagnóstico por imagem , Encefalomalacia/tratamento farmacológico , Receptor 1 de Folato/deficiência , Deficiência de Ácido Fólico/líquido cefalorraquidiano , Deficiência de Ácido Fólico/diagnóstico por imagem , Deficiência de Ácido Fólico/tratamento farmacológico , Homozigoto , Humanos , Leucovorina/uso terapêutico , Imageamento por Ressonância Magnética , Masculino , Convulsões/líquido cefalorraquidiano , Convulsões/diagnóstico por imagem , Convulsões/tratamento farmacológico , Estado Epiléptico/líquido cefalorraquidiano , Estado Epiléptico/diagnóstico por imagem , Estado Epiléptico/tratamento farmacológico , Tetra-Hidrofolatos/líquido cefalorraquidiano , Sequenciamento Completo do Exoma
5.
Eur J Neurosci ; 52(8): 4009-4017, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32506655

RESUMO

Recently, functional studies have demonstrated that legumain (LGMN) cleaves both amyloid ß-protein precursor and tau, promoting senile plaques and formation of neurofibrillary tangles, which may play a crucial role in the pathogenesis of Alzheimer's disease (AD). However, the genetic role of LGMN in AD has not been clearly elucidated. Here, we used Sanger sequencing to investigate the single independent (single-variant association test) and cumulative (gene-based association test) effects of variants in the LGMN gene as potential susceptibility factors for AD, in a cohort comprising 676 AD cases and 365 elderly controls from the Han population of South China. In single-variant association analysis, none of the common variants in LGMN were statistically significant. In gene-based analysis, the LGMN gene also showed no association with AD. The results of our replication study in the Alzheimer's Disease Neuroimaging Initiative cohort also showed no association between LGMN and AD. These findings suggest that the LGMN gene may not be a critical factor for AD development.


Assuntos
Doença de Alzheimer , Idoso , Doença de Alzheimer/genética , Peptídeos beta-Amiloides , China , Cisteína Endopeptidases , Humanos , Polimorfismo de Nucleotídeo Único
6.
Opt Express ; 28(1): 360-368, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-32118964

RESUMO

The storage and retrieval efficiency (SRE) and lifetime of optical quantum memories are two key performance indicators for scaling up quantum information processing. Here, we experimentally demonstrate a cavity-enhanced long-lived optical memory for two polarizations in a cold atomic ensemble. Using electromagnetically induced-transparency (EIT) dynamics, we demonstrate the storages of left-circularly and right-circularly polarized signal light pulses in the atoms, respectively. By making the signal and control beams collinearly pass through the atoms and storing the two polarizations of the signal light as two magnetic-field-insensitive spin waves, we achieve a long-lived (3.5 ms) memory. By placing a low-finesse optical ring cavity around the cold atoms, the coupling between the signal light and the atoms is enhanced, which leads to an increase in SRE. The presented cavity-enhanced storage shows that the SRE is ∼30%, corresponding to an intrinsic SRE of ∼45%.

7.
Opt Express ; 27(20): 27409-27419, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31684508

RESUMO

In this paper, we report a generation of a spin-wave excitation (SWE) with a near-unity (0.996±0.003) probability in a given time (~730 µ s). Such deterministic generation relies on a feedback scheme with a millisecond quantum memory. The millisecond memory is achieved by maximizing the wavelength of the spin wave and storing the SWE as the magnetic-field-insensitive transition. We then demonstrate partial retrievals of the spin wave by applying a first read pulse whose area is smaller than the value of π. The remained SWE is fully retrieved by a second pulse. Anti-correlation function between the detections in the first and second readouts has been measured, which shows that the partial-retrieval operation on the SWE is in the quantum regime. The presented experiment represents an important step towards the realization of the improved DLCZ quantum repeater protocol proposed in Phys. Rev. A 77, 062301 (2008).

8.
Opt Express ; 26(16): 20160-20173, 2018 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-30119330

RESUMO

The enhanced-generation of entanglement between one atomic collective excitation and a single photon (atom-photon) is very important for practical quantum repeaters and quantum networks based on atomic ensembles and linear optics. We present a feedback-loop algorithm based on field programmable gate array (FPGA) to obtain 21.6-fold increase of the generation rate of atom-photon entanglement at the storage time of 51 µs comparing with no feedback protocol. The generation rate of the atom-photon entanglement is ~3190/s (2100/s) for the excitation probability of 1.65% at the storage time of 1 µs (51 µs). The Bell parameter and the fidelity of atom-photon entanglement at the storage time of 1 µs are 2.40 ± 0.02 and 85.5% ± 0.6%, respectively. The detailed FPGA-based feedback-loop algorithm can be flexibly extended to the multiplexing of atom-photon entanglement, which is expected to further increase the generation rate of atom-photon entanglement.

9.
Phys Rev Lett ; 119(13): 130505, 2017 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-29341712

RESUMO

The light-matter quantum interface that can create quantum correlations or entanglement between a photon and one atomic collective excitation is a fundamental building block for a quantum repeater. The intrinsic limit is that the probability of preparing such nonclassical atom-photon correlations has to be kept low in order to suppress multiexcitation. To enhance this probability without introducing multiexcitation errors, a promising scheme is to apply multimode memories to the interface. Significant progress has been made in temporal, spectral, and spatial multiplexing memories, but the enhanced probability for generating the entangled atom-photon pair has not been experimentally realized. Here, by using six spin-wave-photon entanglement sources, a switching network, and feedforward control, we build a multiplexed light-matter interface and then demonstrate a ∼sixfold (∼fourfold) probability increase in generating entangled atom-photon (photon-photon) pairs. The measured compositive Bell parameter for the multiplexed interface is 2.49±0.03 combined with a memory lifetime of up to ∼51 µs.

10.
Sci Rep ; 6: 33959, 2016 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-27667262

RESUMO

We report an experiment in which long-lived quantum memories for photonic polarization qubits (PPQs) are controllably released into any one of multiple spatially-separate channels. The PPQs are implemented with an arbitrarily-polarized coherent signal light pulses at the single-photon level and are stored in cold atoms by means of electromagnetic-induced-transparency scheme. Reading laser pulses propagating along the direction at a small angle relative to quantum axis are applied to release the stored PPQs into an output channel. By changing the propagating directions of the read laser beam, we controllably release the retrieved PPQs into 7 different photonic output channels, respectively. At a storage time of δt = 5 µs, the least quantum-process fidelity in 7 different output channels is ~89%. At one of the output channels, the measured maximum quantum-process fidelity for the PPQs is 94.2% at storage time of δt = 0.85 ms. At storage time of 6 ms, the quantum-process fidelity is still beyond the bound of 78% to violate the Bell's inequality. The demonstrated controllable release of the stored PPQs may extend the capabilities of the quantum information storage technique.

11.
Water Sci Technol ; 73(9): 2119-31, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27148713

RESUMO

The adsorption behavior of natural zeolite was studied in order to determine the adsorption capacity and mass-transfer process of cationic red X-GRL (C(18)H(21)BrN(6)) onto the adsorbent. The adsorption tests to determine both the uptake capacity and the mass-transfer process at equilibrium were performed under batch conditions, which showed rapid uptake in general for the initial 5 min, corresponding to 92% total removal. The equilibrium adsorption capacity value (q(e,cal)) in pseudo-second-order kinetics was 13.51 mg/g at 293 K and the whole adsorption process was governed by physical adsorption with an endothermic, endothermic spontaneous nature. Adsorption tests indicated that the zeolite has great potential as an alternative low-cost material in the treatment of X-GRL drainage. However, the mass-transfer process to determine the rate-controlling steps showed that both film diffusion and pore diffusion were important in controlling the adsorption rate. The adsorption process was governed by film diffusion while pore diffusion was poor because the X-GRL molecules could not penetrate into the zeolite easily. The X-GRL molecules were only adsorbed on the external surface of the zeolite. Hence, to improve the adsorption capacity of natural zeolite further, modification to expand its micropores is necessary.


Assuntos
Poluentes Químicos da Água/química , Zeolitas , Adsorção , Compostos Azo , Cátions , Corantes/química , Difusão , Cinética , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/métodos
12.
Zhongguo Gu Shang ; 27(11): 965-9, 2014 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-25577925

RESUMO

OBJECTIVE: To summarize our experiences in the treatment of type C3 (AO/OTA) distal radius fractures fixed with AO 2.4 mm locking plates combined with percutaneous pinning after manipulative reduction. METHODS: From May 2009 to March 2012, 19 patients (2 cases of both sides) with type C3 (AO/OTA) distal radius fractures were treated with volar locking plates combined with percutaneous pinning for distal radius after manipulative reduction. Among the patients, the average age was (45.3 ± 17.4) years old (ranged, 31 to 66 years old). The fracture were complicated with ulnar styloid fracture in 14 wrists and 6 wrists had distal radioulnar joint instability. All the patients had closed fracture and the mean duration was (6.7 ± 3.5) days (4.5 to 9 days). The Henry approach was applied to expose the fracture site. Joint capsule and ligaments were retained for indirect reduction. After indirect reduction, the poking reduction technique was used to correct the residual compression, and congruence of distal ulnar radial joint was verified under fluorscopic guidance. Styloid process was first pinned percutaneously and then AO 2.4 mm volar locking plate was used to support rigid fixation. The fractures complicated with distal radioulnar joint instability and ulnar styloid fracture were treated with forearm plaster support in supination for 6 weeks. RESULTS: Nineteen patients (21 wrists) were followed up for an average duration of 10.5 months (ranged, 7 to 17 months). Radiographic bone union of distal radius was achieved in all cases, nonunion of the ulnar styloid occurred in 3 cases, and no distal radioulnar joint instability occurred. Tendon irritation was found in 2 cases and disappeared after the internal fixation was removed. The volar tilt, radial angle, radial length, incongruence of articular surface and distal radioulnar joint were observed at the follow-up. According to Batra and Gupta scoring system, 13 wrists were assessed to have a score of more than 80, 5 wrists 70 to 90, 3 wrists less than 70. Meanwhile, the subjective and objective evaluation was executed,range of motion of wrist, residual deformity and complications were observed. According to Sarmiento's modification of the system of Gartland and Werley, 17 wrists got an excellent result, 3 good and 1 fair. CONCLUSION: Type C3 (AO/OTA) distal radius fractures could be managed with manipulative reduction. Locking plate internal fixation combined with percutaneous pinning can offer enough support for early mobilization and rehabilitation, resulting in a better clinical outcome and satisfactory prognosis.


Assuntos
Placas Ósseas , Fixação Interna de Fraturas/métodos , Manipulação Ortopédica/métodos , Fraturas do Rádio/cirurgia , Adulto , Idoso , Humanos , Pessoa de Meia-Idade , Fraturas do Rádio/complicações
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