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1.
Opt Lett ; 49(9): 2249-2252, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38691691

RESUMO

A scheme is proposed to achieve significantly enhanced quantum estimation of optorotational-coupling (ORC) strength by coupling a driven auxiliary cavity to a Laguerre-Gaussian (L-G) rotational cavity, where the ORC originates from the exchange of orbital angular momentum between a L-G light and rotational mirror. The results indicate that, by appropriately designing the auxiliary-cavity mechanism, the estimation error of the ORC parameter is significantly reduced, and revealing the estimation precision has a much stronger thermal noise and dissipation robustness in comparison with the unassisted case. Our study paves the way toward achieving high-precision quantum sensors.

2.
J Endovasc Ther ; : 15266028241253128, 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38733303

RESUMO

OBJECTIVE: The objective was to present our experience on managing mycotic infrarenal abdominal aortic aneurysm (MIAAA) through a retrospective cohort study. METHODS: Data of patients with MIAAA managed in our center from July 2016 to October 2022 were retrospectively analyzed. The diagnosis of MIAAA was made based on: (1) preoperative clinical signs of infection; (2) elevated serologic infection parameters; (3) para-aneurysmal infection features on enhanced computed tomography; and (4) positive blood or tissue cultures. All the patients received standard antibiotic therapy. Surgical management including endovascular aneurysm repair (EVAR), initial EVAR followed by open re-operation, and initial open surgical repair (OSR) were conducted according to disease seriosity, physical condition, and patient's will. Infection index and clinical outcome were evaluated during the follow-up time. RESULTS: A total of 23 patients (21 men; averaged=66.3 years, range=49-79 years) were included, with a mean follow-up time of 19.9 months (range=1-75 months). Bacteria culture from blood or tissue specimen was positive in 15 patients (Salmonella, n=8; Escherichia coli, n=3; methicillin-sensitive Staphylococcus aureus [MSSA], n=1; Klebsiella pneumoniae, n=1; Staphylococcus epidermidis, n=1; Mycobacterium tuberculosis, n=1). Seven patients received OSR as the initial surgical intervention, whereas 14 patients chose EVAR instead. The 2 conservatively managed patients (refused surgery) died within 30 days. The 7 patients who received initial OSR survived till now. Among the 14 patients who underwent initial EVAR, infection deteriorated without exception (14/14, 100%). Three of these patients refused re-operation and died within 6 months. Eleven patients received secondary surgical intervention (10 cases of aneurysm and endograft resection, thorough debridement, subclavian to bi-femoral artery bypass, or in situ aorta reconstruction; 1 case of laparoscopic debridement) and 7 survived the follow-up time. The overall mortality rate was 39.1% (9/23). The mortality rates differed greatly following different intervention methods (merely antibiotic management, 100%; initial open operation, 0%; initial EVAR without secondary operation, 100%; initial EVAR plus secondary operation, 36.4%). CONCLUSIONS: Open surgical repair is still the first choice for hemodynamically stable and low-risk patients. Merely EVAR is related with disastrous results, which should be reserved as a temporary alternative for patients with ruptured aneurysms, hemodynamic instability or high surgical risk, and followed by timely secondary OSR. CLINICAL IMPACT: The management of mycotic or primary-infected aortic aneurysm is challenging; treatment remains controversial. Our center has reviewed our experience over the past 6 years and found that open surgical repair is still the first choice for hemodynamically stable and low-risk patients. Merely endovascular aneurysm repair (EVAR) is related with disastrous results, which should be reserved as a temporary alternative for patients with ruptured aneurysms, hemodynamic instability or high surgical risk, and followed by timely secondary open surgical repair.

3.
Analyst ; 149(3): 729-734, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38131397

RESUMO

Nowadays, easy, convenient, and sensitive sensing strategies are still critical for organophosphorus pesticides in environmental water samples. Herein, a novel organophosphorus pesticide (OP) assay based on acetylcholinesterase (AChE) and a MnO2 nanosheet-mediated CRISPR/Cas12a reaction is reported. The single-strand DNA (ssDNA) activator of CRISPR/Cas12a was simply adsorbed on the MnO2 nanosheets as the nanoswitches of the assay. In the absence of target OPs, AChE hydrolyzed acetylcholine (ATCh) to thiocholine (TCh), which reduced the MnO2 nanosheets to Mn2+, resulting in the release of the activator followed by activation of the CRISPR/Cas12a system. The activated Cas12a thereafter nonspecifically cleaved the FAM/BHQ1-labeled ssDNA (FQ-reporter), producing a fluorescence signal. Upon the addition of target OPs, the hydrolysis of ATCh by AChE was inhibited owing to OPs combining with AChE, and thus effective quantification of OPs could be achieved by measuring the fluorescence changes of the system. As a proof of concept, dichlorvos (DDVP) was chosen as a model OP analyte to address the feasibility of the proposed method. Attributed to the excellent trans-cleavage activity of Cas12a, the fluorescent biosensor exhibits a satisfactory limit of detection (LOD) for DDVP at 0.135 ng mL-1. In addition, the excellent recoveries for the detection of DDVP in environmental water samples demonstrate the applicability of the proposed assay in real sample research.


Assuntos
Técnicas Biossensoriais , Praguicidas , Praguicidas/análise , Compostos Organofosforados , Acetilcolinesterase/genética , Acetilcolinesterase/metabolismo , Sistemas CRISPR-Cas , Diclorvós , Água , Compostos de Manganês , Óxidos , Acetilcolina , Técnicas Biossensoriais/métodos
4.
Child Care Health Dev ; 50(1): e13166, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37648669

RESUMO

BACKGROUND: This study aimed to examine attentional bias (AB) for sad and social rejection words in Chinese left-behind children (LBC) with depression. METHOD: We investigated both stimulus specificity and components of AB in different groups using a cross-sectional design. Data were drawn from a school assessment of depression and anxiety, from which we selected LBC with depression (n = 40), LBC without depression (n = 33), a control group with depression (n = 31), and a control group without depression (n = 37). AB was measured with a dot-probe task covering two stimulus types (sad and rejection). RESULTS: The analysis of AB scores revealed a significant three-way interaction (LBC × depression × word type), F(1, 137) = 4.00, p = 0.047, η2 = 0.028, with depressed non-LBC exhibiting a significant depression × word type interaction, F(1, 66) = 4.67, p = 0.034, η2 = 0.066, while the depression × word type interaction was not significant in LBC, F(1, 71) = 0.18, p = 0.675, η2 = 0.002. Depressed children living with their parents showed AB towards sad words but not rejection words, while depressed LBC showed greater AB towards both rejection and sad words. CONCLUSIONS: The findings provide evidence that an AB towards sad information is critically involved in the depressed LBC. Compared with non-LBC depressed individuals, an AB for rejection may be involved as a risk factor in the LBC. It sheds light on the effective intervention programmes for LBC's depression and have important practical significance for reducing depression and improving the mental health of LBC.


Assuntos
Viés de Atenção , Depressão , Criança , Humanos , Estudos Transversais , Ansiedade , China
5.
Anticancer Drugs ; 34(1): 29-43, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-35946506

RESUMO

Cisplatin (DDP) resistance limits therapeutic efficacy in patients diagnosed with ovarian cancer. Purvalanol A (Pur) is a novel cyclin-dependent kinase (CDK) inhibitor that has been demonstrated to induce apoptosis in various cancer cells. The present study investigated the effect of the combination treatment of Pur and DDP, and the potential anticancer mechanisms in epithelial ovarian cancer (EOC) cells in vitro and in vivo . We found that Pur enhanced the anti-tumor efficacy of cisplatin in EOC cells. The combination of Pur and DDP had more significant effects on apoptosis induction in EOC cells compared with the individual-treatment groups and the control group. We further demonstrated that the combination of Pur and DDP may trigger apoptosis and autophagy in EOC cells by inducing reactive oxygen species (ROS). And the ROS/Akt/mammalian target of rapamycin signaling pathway as a potential mechanism for the initiation of autophagy induced by combination therapy. Similar results were observed in vivo . These results demonstrated that Pur sensitized the response of EOC cells to cisplatin in vitro and in vivo , reversing the resistance to cisplatin in ovarian cancer.


Assuntos
Antineoplásicos , Neoplasias Ovarianas , Humanos , Feminino , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Espécies Reativas de Oxigênio/metabolismo , Resistencia a Medicamentos Antineoplásicos , Proliferação de Células , Neoplasias Ovarianas/patologia , Apoptose , Carcinoma Epitelial do Ovário/tratamento farmacológico , Carcinoma Epitelial do Ovário/patologia , Inibidores de Proteínas Quinases/farmacologia , Linhagem Celular Tumoral , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico
6.
Cereb Cortex ; 32(21): 4857-4868, 2022 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-35078209

RESUMO

Mild cognitive impairment in Parkinson's disease (PD-M) is related to a high risk of dementia. This study explored the whole-brain functional networks in early-stage PD-M. Forty-one patients with PD classified as cognitively normal (PD-N, n = 17) and PD-M (n = 24) and 24 demographically matched healthy controls (HC) underwent clinical and neuropsychological evaluations and resting-state functional magnetic resonance imaging. The global, regional, and modular topological characteristics were assessed in the brain functional networks, and their relationships to cognitive scores were tested. At the global level, PD-M and PD-N exhibited higher characteristic path length and lower clustering coefficient, local and global efficiency relative to HC. At the regional level, PD-M and PD-N showed lower nodal centrality in sensorimotor regions relative to HC. At the modular level, PD-M showed lower intramodular connectivity in default mode and cerebellum modules, and lower intermodular connectivity between default mode and frontoparietal modules than PD-N, correlated with Montreal Cognitive Assessment scores. Early-stage PD patients showed weaker small-worldization of brain networks. Modular connectivity alterations were mainly observed in patients with PD-M. These findings highlight the shared and distinct brain functional network dysfunctions in PD-M and PD-N, and yield insight into the neurobiology of cognitive decline in PD.


Assuntos
Disfunção Cognitiva , Doença de Parkinson , Humanos , Disfunção Cognitiva/patologia , Encéfalo , Imageamento por Ressonância Magnética , Mapeamento Encefálico
7.
Opt Express ; 30(23): 41898-41910, 2022 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-36366654

RESUMO

We proposed a method based on the Brillouin optical time domain analysis (BOTDA) system to demodulate the length changes of the heating region using the intensity of probe light, under the premise that the temperature in the heating region does not change and the Brillouin frequency shift (BFS) of the heating region is known. This method can realize the recognition of small length under the condition of wide pulse width. The theoretical analysis shows that the different lengths of the heating region will lead to different gains when the spatial resolution corresponding to the pulse width of the pulsed light is larger than the length of the heating region. And through theoretical derivation and simulation, it is concluded that the relationship between the intensity of probe light and the length of the heating region satisfies the exponential growth. Further experiments verify that the exponential growth is approximately linear in the range of small length changes. The length of the heating region can be inversely deduced by using the linear relationship by detecting the intensity of probe light. When the length of sensing fiber is 100 m and the heating region changes from 2 cm to 8 cm, 1 cm heating region changes can be identified.

8.
Anal Chem ; 93(17): 6770-6778, 2021 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-33885275

RESUMO

In this work, a convenient and flexible assay for colorimetric and electrochemiluminescence (ECL) sensing of phosphate was proposed based on the enzymatic behavior regulation of the cobalt oxyhydroxide (CoOOH) nanosheet. CoOOH as a novel nanoenzyme exhibited a peroxidase-like activity, which could catalyze different substrates such as 2, 2'-azinobis-3-ethylbenzthiazoline-6-sulfonate (ABTS) and 4-chloro-1-naphthol (4-CN) with hydrogen peroxide (H2O2) as the electron acceptor. Phosphate could specifically regulate the enzymatic behavior of the CoOOH nanosheet via the deactivating effect. A high level of phosphate enabled a weak color change of ABTS, which offered a "turn-off" model of the colorimetric assay with a limit of detection of 0.673 µM. Based on the similar enzymatic behavior, this strategy could then be applied in the ECL assay utilizing l-arginine-6-aza-2-thiothymine-protected gold nanoclusters (Arg-ATT-AuNCs) as ECL signal indicators. Specifically, 4-CN was catalyzed to generate the precipitate and lead to the quenching on ECL emission. Different from colorimetric behavior, phosphate with a high concentration could induce strong ECL performance, which enabled the "turn-on" model of the ECL assay with a more sensitive determination down to 0.434 nM. This flexible enzymatic behavior regulation could then allow the phosphate measurement in environmental samples including tap water and river water with satisfactory accuracy, which holds the potential in the field of environmental protection.


Assuntos
Colorimetria , Peróxido de Hidrogênio , Cobalto , Óxidos , Fosfatos
9.
Hum Brain Mapp ; 42(15): 5101-5112, 2021 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-34322939

RESUMO

Patients with Parkinson's disease with mild cognitive impairment (PD-M) progress to dementia more frequently than those with normal cognition (PD-N), but the underlying neurobiology remains unclear. This study aimed to define the specific morphological brain network alterations in PD-M, and explore their potential diagnostic value. Twenty-four PD-M patients, 17 PD-N patients, and 29 healthy controls (HC) underwent a structural MRI scan. Similarity between interregional gray matter volume distributions was used to construct individual morphological brain networks. These were analyzed using graph theory and network-based statistics (NBS), and their relationship to neuropsychological tests was assessed. Support vector machine (SVM) was used to perform individual classification. Globally, compared with HC, PD-M showed increased local efficiency (p = .001) in their morphological networks, while PD-N showed decreased normalized path length (p = .008). Locally, similar nodal deficits were found in the rectus and lingual gyrus, and cerebellum of both PD groups relative to HC; additionally in PD-M nodal deficits involved several frontal and parietal regions, correlated with cognitive scores. NBS found that similar connections were involved in the default mode and cerebellar networks of both PD groups (to a greater extent in PD-M), while PD-M, but not PD-N, showed altered connections involving the frontoparietal network. Using connections identified by NBS, SVM allowed discrimination with high accuracy between PD-N and HC (90%), PD-M and HC (85%), and between the two PD groups (65%). These results suggest that default mode and cerebellar disruption characterizes PD, more so in PD-M, whereas frontoparietal disruption has diagnostic potential.


Assuntos
Cerebelo/patologia , Córtex Cerebral/patologia , Disfunção Cognitiva/fisiopatologia , Rede de Modo Padrão/patologia , Substância Cinzenta/patologia , Rede Nervosa/patologia , Doença de Parkinson/patologia , Idoso , Cerebelo/diagnóstico por imagem , Córtex Cerebral/diagnóstico por imagem , Disfunção Cognitiva/etiologia , Rede de Modo Padrão/diagnóstico por imagem , Feminino , Substância Cinzenta/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Rede Nervosa/diagnóstico por imagem , Doença de Parkinson/complicações , Doença de Parkinson/diagnóstico por imagem
10.
Hum Brain Mapp ; 42(10): 3156-3167, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33769638

RESUMO

Neuroimaging studies using a variety of techniques have demonstrated abnormal patterns of spontaneous brain activity in patients with essential tremor (ET). However, the findings are variable and inconsistent, hindering understanding of underlying neuropathology. We conducted a meta-analysis of whole-brain resting-state functional neuroimaging studies in ET compared to healthy controls (HC), using anisotropic effect-size seed-based d mapping, to identify the most consistent brain activity alterations and their relation to clinical features. After systematic literature search, we included 13 studies reporting 14 comparisons, describing 286 ET patients and 254 HC. Subgroup analyses were conducted considering medication status, head tremor status, and methodological factors. Brain activity in ET is altered not only in the cerebellum and cerebral motor cortex, but also in nonmotor cortical regions including prefrontal cortex and insula. Most of the results remained unchanged in subgroup analyses of patients with head tremor, medication-naive patients, studies with statistical threshold correction, and the large subgroup of studies using functional magnetic resonance imaging. These findings not only show consistent and robust abnormalities in specific brain regions but also provide new information on the biology of patient heterogeneity, and thus help to elucidate the pathophysiology of ET.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Conectoma , Tremor Essencial/diagnóstico por imagem , Tremor Essencial/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Descanso
11.
Neuroradiology ; 63(9): 1501-1510, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33782719

RESUMO

PURPOSE: To use structural magnetic resonance imaging and graph theory approaches to investigate the topological organization of the brain morphological network based on gray matter in essential tremor, and its potential relation to disease severity. METHODS: In this prospective study conducted from November 2018 to November 2019, 36 participants with essential tremor and 37 matched healthy controls underwent magnetic resonance imaging. Brain networks based on the morphological similarity of gray matter across regions were analyzed using graph theory. Nonparametric permutation testing was used to assess group differences in topological metrics. Support vector machine was applied to the gray matter morphological matrices to classify participants with essential tremor vs. healthy controls. RESULTS: Compared with healthy controls, participants with essential tremor showed increased global efficiency (p < 0.01) and decreased path length (p < 0.01); abnormal nodal properties in frontal, parietal, and cerebellar lobes; and disconnectivity in cerebello-thalamo-cortical network. The abnormal brain nodal centralities (left superior cerebellum gyrus; right caudate nucleus) correlated with clinical measures, both motor (Fahn-Tolosa-Marìn tremor rating, p = 0.017, r = - 0.41) and nonmotor (Hamilton depression scale, p = 0.040, r = - 0.36; Hamilton anxiety scale, p = 0.008, r = - 0.436). Gray matter morphological matrices classified individuals with high accuracy of 80.0%. CONCLUSION: Participants with essential tremor showed randomization in global properties and dysconnectivity in the cerebello-thalamo-cortical network. Participants with essential tremor could be distinguished from healthy controls by gray matter morphological matrices.


Assuntos
Tremor Essencial , Preparações Farmacêuticas , Encéfalo/diagnóstico por imagem , Tremor Essencial/diagnóstico por imagem , Substância Cinzenta/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Estudos Prospectivos
12.
MAGMA ; 34(2): 201-212, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32661843

RESUMO

OBJECTIVES: Essential tremor with resting tremor (rET) often exhibits severer clinical features and more extensive functional impairment than essential tremor without resting tremor (ETwr). However, the pathophysiology of rET is still unclear. This study aims to use resting-state functional magnetic resonance imaging (rs-fMRI) to explore the alterations of brain activity between the drug-naïve patients of rET and ETwr. METHODS: We recruited 19 patients with rET, 31 patients with ETwr and 25 healthy controls (HCs) to undergo a 3.0-T rs-fMRI examination. The differences of regional brain spontaneous activity between the rET, ETwr and HCs, as well as between total ET (rET + ETwr) and HCs were measured by amplitude of low-frequency fluctuation (ALFF) and fractional ALFF (fALFF). The relationships between the altered brain measurements and the clinical scores were analyzed. RESULTS: Compared with HCs, both ET subgroups showed significantly decreased ALFF or fALFF values in the basal ganglia, inferior orbitofrontal gyrus and insula. The rET group specifically showed decreased ALFF values in the hippocampus and motor cortices, while the ETwr group specifically evidenced increased ALFF and fALFF values in the cerebellum. DISCUSSION: Regional spontaneous activity in rET and ETwr share common changes and have differences, which may suggest that the functional activities in the limbic system and cerebellum are different between the two subtypes. Improved insights into rET and ETwr subtypes and the different brain spontaneous activity will be valuable for improving our understanding of the pathophysiology of the disease.


Assuntos
Tremor Essencial , Imageamento por Ressonância Magnética , Encéfalo , Mapeamento Encefálico , Tremor Essencial/diagnóstico por imagem , Humanos , Tremor
13.
Acta Neurol Scand ; 142(1): 74-82, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32176316

RESUMO

BACKGROUND: There have been few comprehensive scale studies on the non-motor symptoms (NMS) of patients with essential tremor (ET) with head tremor (ETh) and those with ET without head tremor (ETol). We aimed to explore the motor symptoms and NMS of these two subgroups. METHODS: We enrolled 199 patients with ET (125, ETol; 74 ETh) and 132 healthy controls. We evaluated motor symptoms using the Fahn-Tolosa-Marin Tremor Rating Scale (TRS) and NMS using the Non-Motor Symptom Scale (NMSS). We compared NMSS scores and the prevalence of each NMS between the patient subgroups. Finally, we conducted a logistic regression analysis of the correlation between head tremor and NMS severity, as well as other determinants. RESULTS: There were no significant between-subgroup differences in demographic characteristics. Further, they presented similar tremor clinical manifestation; however, the ETh subgroup showed a higher prevalence of rest tremor, feeling of sadness, forgetting things or events, and swallowing difficulty, as well as TRS scores, compared with the ETol subgroup. Both patient subgroups showed high scores and prevalence (>50%) in difficulty falling asleep. Logistic regression analysis indicated age as a tremor severity determinant; further, head tremor and tremor severity were NMS determinants. CONCLUSION: Both patient subgroups presented various NMS including sleep disturbances, cognitive deficits, and affective disorders. The ETh subgroup showed a high prevalence of certain NMS aspects including memory and affective disorder; further, they had aggravated NMS. ET with both upper limb tremor and head tremor may be regarded as a more severe clinical subtype.


Assuntos
Tremor Essencial/complicações , Adulto , Idoso , Transtornos Cognitivos/epidemiologia , Transtornos Cognitivos/etiologia , Transtornos de Deglutição/epidemiologia , Transtornos de Deglutição/etiologia , Feminino , Cabeça , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Adulto Jovem
14.
Anal Chem ; 91(16): 10672-10678, 2019 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-31355629

RESUMO

In this work, based on mesoporous silica containers (MSNs) with the programmed enzyme-free DNA assembly amplification of catalytic hairpin assembly (CHA) and hybridization chain reaction (HCR), an ultrasensitive electrochemical sensing platform with low background is developed for the detection of microRNA (miRNA). Herein, the electrochemical reporter methylene blue (MB) was sealed in the pores of MSNs by the double-stranded DNA (dsDNA) gate of hairpin DNA H1 and anchor DNA. In the absence of target, neither the CHA nor the HCR process happened, which enabled a low background. After target was added, DNA H1 was displaced from the MSNs surface and participated in the CHA process with the assistance of hairpin DNA H2, which accelerated the release of MB from the MSNs pore. Meanwhile, the CHA products H1-H2 were hybridized with the capture probes (SH-CP) on the electrode surface, which further initiated the HCR process. The released MB from the MSNs will effectively intercalate into long dsDNA polymers of HCR products, resulting in a significant electrochemical response. Taking miRNA-21 as the model target, the proposed sensing platform achieves a satisfactory detection limit down to 0.037 fM, which is lower than that of electrochemical assay with amplification methods. In addition, the strategy shows good selectivity against other miRNAs and is capable in practical analytes. Benefitting from the features of being label-free and enzyme-free and having low background, high sensitivity, and selectivity, this strategy shows great potential in bioanalysis and clinical diagnostics.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , MicroRNAs/análise , Técnicas de Amplificação de Ácido Nucleico , Dióxido de Silício/química , Catálise , Eletrodos , Humanos , Azul de Metileno/química , Tamanho da Partícula , Porosidade , Propriedades de Superfície
15.
J Hum Genet ; 64(3): 215-219, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30617279

RESUMO

Distal spinal muscular atrophy (dSMA) is a rare clinically and genetically heterogeneous group of inherited disorders characterized by progressive distal muscle weakness and wasting. So far, more than 65% of patients with dSMA have undiscovered genetic mutations. Recently, compound heterozygous mutations in the vaccinia-related kinase 1 (VRK1) gene have been identified for the first time in two siblings with adult-onset dSMA from an Ashkenazi Jewish family. Here, we also report two affected siblings with adult-onset dSMA in a Chinese family. Whole exome sequencing and subsequent Sanger sequencing identified a novel nonsense mutation (c.1124G >A, p.W375*) in exon 12 of the VRK1 gene, co-segregating with the dSMA phenotype in an autosomal recessive pattern. In conclusion, our findings identify a novel nonsense mutation p.W375* in the VRK1 gene in a Chinese family with autosomal recessive dSMA and broaden the genetic spectrum of VRK1-associated dSMA.


Assuntos
Códon sem Sentido , Peptídeos e Proteínas de Sinalização Intracelular/genética , Atrofia Muscular Espinal/genética , Proteínas Serina-Treonina Quinases/genética , Adolescente , Adulto , Idade de Início , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Linhagem , Fenótipo , Prognóstico
16.
Opt Express ; 27(21): 29479-29490, 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31684208

RESUMO

We theoretically investigate the entanglement between two macroscopic rotating mirrors in a Laguerre-Gaussian (L-G) cavity, in which they exchange orbital angular momentum with a same L-G cavity mode, and we examine the influence of various factors such as angular frequencies of two mirrors, effective detuning, temperature and orbital angular momentum of L-G cavity mode on the entanglement. The results show that in some range of mirrors' angular frequencies the entanglement will appear and has strong robustness. And we also study the range of effective detuning and the minimum orbital angular momentum of the L-G cavity mode required to generate entanglement.

17.
Opt Express ; 26(7): 8252-8259, 2018 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-29715794

RESUMO

While augmenting network on chips (NoC) with photonic links enables high-bandwidth communication, the overhead for photonics is rather large, mainly driven by bulky footprints and the multi-functionality of transceivers. The latter requires, in addition to a photon source, signal modulation and detection. If the NoC were photonically augmented at every network point to enable all-to-all connectivity, the resulting photonic overhead would be excessive. Besides, the high bandwidth of a single optical bus may be sufficient to supply the data-sharing demand of a network. Spatial signal routing is a necessary function of data communication in NoCs. However, if photonic links are used to augment electronics, an energy-costly optical-electrical-optical (OEO) conversion is required since routing is currently executed in the electronic domain. Here we show a novel integrated broadband hybrid photonic-plasmonic device termed an MO detector featuring dual light modulation and detection. With 10 dB extinction ratio and 0.8 dB insertion loss at the modulation state and 0.7 A/W responsivity at the detection state based on the finite-different time-domain simulation, this transceiver-like device (i) eliminates the OEO conversion, (ii) reduces optical losses from photodetectors via bypassing the photodetector when not needed, and (iii) enables cognitive routing strategies for network-on-chips. As such, the MO detector acts as a micrometer-compact transceiver for next-generation NoCs.

18.
Opt Lett ; 43(9): 2026-2029, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29714737

RESUMO

The residue number system (RNS) enables dimensionality reduction of an arithmetic problem by representing a large number as a set of smaller integers, where the number is decomposed by prime number factorization. These reduced problem sets can then be processed independently and in parallel, thus improving computational efficiency and speed. Here, we show an optical RNS hardware representation based on integrated nanophotonics. The digit-wise shifting in RNS arithmetic is expressed as spatial routing of an optical signal in 2×2 hybrid photonic-plasmonic switches. Here, the residue is represented by spatially shifting the input waveguides relative to the routers' outputs, where the moduli are represented by the number of waveguides. By cascading the photonic 2×2 switches, we design a photonic RNS adder and a multiplier forming an all-to-all sparse directional network. The advantage of this photonic arithmetic processor is the short (10's ps) computational execution time given by the optical propagation delay through the integrated nanophotonic router. Furthermore, we show how photonic processing in-the-network leverages the natural parallelism of optics such as wavelength-division-multiplexing in this RNS processor. A key application for such a photonic RNS engine is the functional analysis of convolutional neural networks.

19.
J Nanosci Nanotechnol ; 18(6): 3888-3892, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29442723

RESUMO

Graphene oxide nanosheets was prepared, modification with 3-aminopropyltriethoxysilane and used as the carrier for immobilization of NADH oxidase (NOX) from Streptococcus mutans. The prepared nanosheets were characterized with FTIR. A high immobilization yield of 92% and activity recovery of 91% were achieved at pH 7.0 and 25 °C. The thermostability of the immobilized NOX was improved about 60% compared with the free enzyme. And the immobilized NOX preserved about 92% of its initial activity after 500 h storage at 4 °C, while free NOX was totally denatured after 200 h at the same conditions. These results indicate that NH2-functionalized graphene oxide nanosheets has a good potential as carrier for immobilization of proteins, especially enzymes.


Assuntos
Enzimas Imobilizadas , Grafite , Complexos Multienzimáticos , NADH NADPH Oxirredutases , Nanopartículas , Óxidos
20.
J Nanosci Nanotechnol ; 18(12): 8232-8239, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30189942

RESUMO

Lithium ion batteries with graphite negative electrodes have been developed to date due to their low power density, which limits their application in many cases, however. Nanoscale Li4Ti5O12 has higher power density than conventional graphite anode materials. In order to ensure that the full-cell system has high power and high energy, cathode materials are very important. In this paper, three different cathode materials, LiNi0.8Co0.15Al0.05O2 (NCA), LiNi0.6Co0.2Mn0.2O2 (NCM622), and LiCoO2 (LCO), were used to conduct a comprehensive study, and optimal NCA-Li4Ti5O12(LTO) full battery system was selected under high power conditions. On the basis, in order to further increase battery power density, and in combination with the mechanism of the supercapacitor non-Faradic energy storage, polyaniline activated carbon material (PANI-AC) with excellent capacitance characteristics was prepared. In the end, we proposed a new type of hybrid battery capacitor system with high power and high energy.

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