Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 39
Filtrar
1.
CNS Neurosci Ther ; 2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34551193

RESUMO

AIM: The role of vascular dementia (VaD)-associated genes in Alzheimer's disease (AD) remains elusive despite similar clinical and pathological features. We aimed to explore the relationship between these genes and AD in the Chinese population. METHODS: Eight VaD-associated genes were screened by a targeted sequencing panel in a sample of 3604 individuals comprising 1192 AD patients and 2412 cognitively normal controls. Variants were categorized into common variants and rare variants according to minor allele frequency (MAF). Common variant (MAF ≥ 0.01)-based association analysis was conducted by PLINK 1.9. Rare variant (MAF < 0.01) association study and gene-based aggregation testing of rare variants were performed by PLINK 1.9 and Sequence Kernel Association Test-Optimal (SKAT-O test), respectively. Age at onset (AAO) and Mini-Mental State Examination (MMSE) association studies were performed with PLINK 1.9. Analyses were adjusted for age, gender, and APOE ε4 status. RESULTS: Four common COL4A1 variants, including rs874203, rs874204, rs16975492, and rs1373744, exhibited suggestive associations with AD. Five rare variants, NOTCH3 rs201436750, COL4A1 rs747972545, COL4A1 rs201481886, CST3 rs765692764, and CST3 rs140837441, showed nominal association with AD risk. Gene-based aggregation testing revealed that HTRA1 was nominally associated with AD. In the AAO and MMSE association studies, variants in GSN, ITM2B, and COL4A1 reached suggestive significance. CONCLUSION: Common variants in COL4A1 and rare variants in HTRA1, NOTCH3, COL4A1, and CST3 may be implicated in AD pathogenesis. Besides, GSN, ITM2B, and COL4A1 are probably involved in the development of AD endophenotypes.

2.
Vet Microbiol ; 261: 109208, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34419775

RESUMO

African swine fever virus (ASFV) is a large nucleoplasmic DNA virus, in which the genome is around 170-198 kilobases (kb). More than 50 % genes have unknown functions. Here, MGF100-1R gene is chosen to study the primary function and sublocalization. The gene was located at the left variable region of the ASFV genome that belongs to MGF100 families. It located at the cytoplasm without cytotoxic activities. However, it related to induce the transcriptional levels of pro-inflammatory cytokines. A deletion mutant of MGF100-1R gene was constructed based on ASFV Chinese strain GZ201801. The recombinant deletion mutant (ASFV△MGF100-1R) was demonstrated in vitro that the gene is non-essential for virus replication with a similar replication kinetics in bone marrow-derived macrophages (BMDMs) cell cultures when compared to parental virus. In vivo evaluation, ASFV△MGF100-1R was inoculated intramuscularly and led to a similar pathogenesis that caused by the parental ASFV GZ201801, confirming that deletion of MGF100-1R gene from the ASFV genome does not impact virulence.

3.
NPJ Genom Med ; 6(1): 69, 2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34389718

RESUMO

Neurodegenerative dementias are a group of diseases with highly heterogeneous pathology and complicated etiology. There exist potential genetic component overlaps between different neurodegenerative dementias. Here, 1795 patients with neurodegenerative dementias from South China were enrolled, including 1592 with Alzheimer's disease (AD), 110 with frontotemporal dementia (FTD), and 93 with dementia with Lewy bodies (DLB). Genes targeted sequencing analysis were performed. According to the American College of Medical Genetics (ACMG) guidelines, 39 pathogenic/likely pathogenic (P/LP) variants were identified in 47 unrelated patients in 14 different genes, including PSEN1, PSEN2, APP, MAPT, GRN, CHCHD10, TBK1, VCP, HTRA1, OPTN, SQSTM1, SIGMAR1, and abnormal repeat expansions in C9orf72 and HTT. Overall, 33.3% (13/39) of the variants were novel, the identified P/LP variants were seen in 2.2% (35/1592) and 10.9% (12/110) of AD and FTD cases, respectively. The overall molecular diagnostic rate was 2.6%. Among them, PSEN1 was the most frequently mutated gene (46.8%, 22/47), followed by PSEN2 and APP. Additionally, the age at onset of patients with P/LP variants (51.4 years), ranging from 30 to 83 years, was ~10 years earlier than those without P/LP variants (p < 0.05). This study sheds insight into the genetic spectrum and clinical manifestations of neurodegenerative dementias in South China, further expands the existing repertoire of P/LP variants involved in known dementia-associated genes. It provides a new perspective for basic research on genetic pathogenesis and novel guiding for clinical practice of neurodegenerative dementia.

4.
Environ Pollut ; 287: 117557, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34167001

RESUMO

Zearalenone (ZEA) is an estrogenic toxin produced by Fusarium strains, that is widely present in crops, and endangers the reproductive system of animals. Tannic acid (TA) is a natural polyphenolic substance that is widespread in the roots, stems, and leaves of plants, and has special pharmacological activity. This study was designed to investigate the therapeutic effect of TA on ZEA-induced ovarian damage in mice and to explore the molecular mechanism involved. Ninety healthy Kunming female mice were divided into six equal groups. All the groups but the control group were administered daily with ZEA [10 mg/kg body weight (bw)] orally, for 7 days, to induce damage to the reproductive system. Some groups were also administered with TA (50, 100, and 200 mg/bw) for 7 days. Mice were euthanized 24 h later to allow for collection of serum and ovaries. TA can effectively alleviate the appearance of congestion and redness of the ovary, caused by ZEA, and increase the number of healthy growing follicles. Moreover, the estrogen content and the levels of MDA and ROS in the ovaries can be effectively reduced by TA. It can also reduce the apoptosis of ovarian cells, decreases the protein expression of the estrogen receptor, Fas, Fasl, caspase-3, caspase-8, caspase-9, and Bax, and increases the protein expression of Bcl-2. Our study indicates that TA reduces the strong estrogen and oxidative damage induced by ZEA, and these therapeutic effects may be partially mediated by the death receptor and mitochondrial apoptosis signaling pathway.


Assuntos
Zearalenona , Animais , Apoptose , Feminino , Camundongos , Receptores de Morte Celular , Transdução de Sinais , Taninos , Zearalenona/toxicidade
5.
Neurobiol Aging ; 2021 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-34172279

RESUMO

Alzheimer's disease (AD) and frontotemporal dementia (FTD) overlap clinically and pathologically. However, the role of FTD-associated genes in patients with AD remained unclear. To explore the relationship between FTD-associated genes and AD risk, we investigated 14 FTD-associated genes via targeted next-generation sequencing panel or whole-genome sequencing in a total of 721 AD patients and 1391 controls. Common variant-based association analysis and gene-based association test of rare variants were performed by PLINK 1.9 and Sequence Kernel Association Test-Optimal (SKAT-O test) respectively. As a result, 2 common variants, UBQLN1 rs1044175 (p value = 2.76 × 10-4) and MAPT rs2258689 (p value = 5.71 × 10-4), differed significantly between AD patients and controls. Additionally, gene-based analysis aggregating rare variants demonstrated that HNRNPA1 reached statistical significance in the SKAT-O test (p value = 2.24 × 10-3). Protein-protein interaction analysis showed that UBQLN1, MAPT, and HNRNPA1 interacted with proteins encoded by well-recognized AD-associated genes. Our study indicated that UBQLN1, MAPT, and HNRNPA1 are implicated in the pathogenesis of AD in the mainland Chinese population.

6.
CNS Neurosci Ther ; 27(8): 930-940, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33942994

RESUMO

AIMS: NOTCH3 gene mutations predominantly cause cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy, a common etiology of subcortical vascular dementia (SVaD). Besides, there may be a pathogenic link between NOTCH3 variants and Alzheimer's disease (AD). We aimed to study the role of NOTCH3 variants in AD and SVaD patients. METHODS: We recruited 763 patients with dementia (667 AD and 96 SVaD) and 365 healthy controls from the Southern Han Chinese population. Targeted capture sequencing was performed on NOTCH3 coding and adjacent intron regions to detect the pathogenic variants in AD and SVaD. The relationship between common or rare NOTCH3 variants and AD was further analyzed using Plink1.9. RESULTS: Five known pathogenic variants (p.R182C, p.C201S, p.R544C, p.R607C, and p.R1006C) and two novel likely pathogenic variants (p.C201F and p.C1061F) were detected in 16 SVaD patients. Additionally, no pathogenic or likely pathogenic variants were found in AD patients. NOTCH3 was not associated with AD in either single-variant association analysis or gene-based association analysis. CONCLUSION: Our findings broaden the mutational spectrum of NOTCH3 and validate the pathogenic role of NOTCH3 mutations in SVaD, but do not support the notion that NOTCH3 variation influences the risk of AD.

7.
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
8.
Rev Sci Instrum ; 92(1): 015005, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33514220

RESUMO

Intravascular ultrasound (IVUS) has become a useful tool in the detection of coronary artery disease. However, non-uniform rotation distortion (NURD) reduces the image quality. In order to suppress the influence of NURD, a piezoelectric motor that can meet the requirements of IVUS catheters has been proposed. The motor has a diameter of 1 mm and a length of 10 mm using the new polarization direction proposed in the paper. A 45° mirror is fixed on the top of the motor to reflect the ultrasound transmitted from the transducer. The manufacture and drive of the piezoelectric motor is simple, and the maximum speed of the piezoelectric motor can reach 6450 rpm under the voltage of 20Vp-p. The minimum power required by the rotating motor is only 0.038 W, which can be directly driven by the signal generator without a power amplifier. The motor can operate at a low voltage and still has a high and stable speed. Meanwhile, the speed of the motor is controllable and has a satisfactory stability with a maximum angular error of 8°. The images detected by the cooperation of the motor and the ultrasonic transducer are also shown, which indicates that the motor has the rotational stability that meets the imaging requirements and the potential for application in the IVUS catheter to help improve the image quality of the coronary arteries and prevent and help treat potential diseases.


Assuntos
Cateteres , Vasos Coronários/diagnóstico por imagem , Desenho de Equipamento , Ultrassonografia/instrumentação , Eletricidade , Humanos
9.
Front Aging Neurosci ; 12: 581524, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33192475

RESUMO

Amyloid protein deposition is a common mechanism of hereditary amyloidosis (HA) and Alzheimer's disease (AD). Mutations of gelsolin (GSN), cystatin C (CST3), transthyretin (TTR), and integral membrane protein 2B (ITM2B) genes can lead to HA. But the relationship is unclear between these genes and AD. Genes targeted sequencing (GTS), including GSN, CST3, TTR, and ITM2B, was performed in a total of 636 patients with clinical AD and 365 normal controls from China. As a result, according to American College of Medical Genetics and Genomics (ACMG) guidelines, two novel likely pathogenic frame-shift mutations (GSN:c.1036delA:p.K346fs and GSN:c.8_35del:p.P3fs) were detected in five patients with AD, whose initial symptom was memory decline, accompanied with psychological and behavioral abnormalities later. Interestingly, the patient with K346fs mutation, presented cerebral ß-amyloid protein deposition, had an early onset (48 years) and experienced rapid progression, while the other four patients with P3fs mutation had a late onset [(Mean ± SD): 69.50 ± 5.20 years] and a long course of illness [(Mean ± SD): 9.24 ± 4.86 years]. Besides, we also discovered 17 variants of uncertain significance (VUS) in these four genes. To our knowledge, we are the first to report AD phenotype with GSN mutations in patients with AD in the Chinese cohort. Although mutations in the GSN gene are rare, it may explain a small portion of clinically diagnosed AD.

10.
Front Aging Neurosci ; 12: 584801, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33240075

RESUMO

The genes involved in the metabolic pathways of amyloid-ß (Aß) and tau proteins significantly influence the etiology of Alzheimer's disease (AD). Various studies have explored the associations between some of these genes and AD in the Caucasian population; however, researches regarding these associations remain limited in the Chinese population. To systematically evaluate the associations of these genes with AD, we investigated 19 genes involved in the metabolism of Aß and tau based on previous studies selected using the PubMed database. This study included 372 patients with sporadic late-onset AD (sLOAD) and 345 cognitively healthy individuals from southern China. The results were replicated in the International Genomics of Alzheimer's Project (IGAP). Protein-protein interactions were determined using the STRING v11 database. We found that a single-nucleotide polymorphism, rs11682128, of BIN1 conferred susceptibility to sLOAD after adjusting for age, sex, and APOE ε4 status and performing the Bonferroni correction {corrected P = 0.000153, odds ratio (OR) [95% confidence interval (CI)] = 1.403 (1.079-1.824)}, which was replicated in the IGAP. Protein-protein interactions indicated that BIN1 was correlated with MAPT. Moreover, rare variants of NEP and FERMT2 (0.0026 < corrected P < 0.05), and the Aß degradation, tau pathology, and tau phosphatase pathways (0.01 < corrected P < 0.05), were nominally significantly associated with sLOAD. This study suggested that the genes involved in the metabolic pathways of Aß and tau contributed to the etiology of sLOAD in the southern Han Chinese population.

11.
Ann Clin Transl Neurol ; 7(10): 1985-1995, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32941707

RESUMO

OBJECTIVE: To investigate the impact of rare variants underlying neurodegenerative-related genes to familial Alzheimer's disease (AD). METHODS: We performed targeted sequencing of 277 neurodegenerative-related genes on probands from 75 Chinese AD families non-carrying causative mutation of dementia genes. Rare coding variants segregated in families were tested for association in an independent cohort of 506 patients with sporadic AD and 498 cognitively normal controls. East Asians data from the Exome Aggregation Consortium (ExAC) were used as a reference control. RESULTS: A novel rare variant, P410S of PLD3 was found in an early-onset AD family. LRRK2 I2012T, a causative mutation of Parkinson's disease, was identified in another early-onset AD family. Missense variants in ABCA7 (P143S and A1507T) and CR1(T239M) were significantly associated with familial AD (P = 0.005437, 0.001383, 0.000549), a missense variant in TREM2(S183C) was significantly associated with AD (P = 0.000396) when compared with the East Asian controls in ExAC database. A non-frameshift variant in FUS (G223del) was frequent in AD cases and significantly associated with familial AD (P = 0.008). INTERPRETATION: Multiple rare coding variants of causal and risk neurodegenerative genes were presented in clinically diagnosed AD families that may confer risk of AD. Our data supported that the clinical, pathological, and genetic architectures of AD, PD, and FTD/ALS may overlapping. We propose that targeted sequencing on neurodegenerative-related genes is necessary for genetically unclear AD families.

12.
Parkinsonism Relat Disord ; 80: 65-72, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32961396

RESUMO

INTRODUCTION: Genetic inheritance plays key roles in patients with ataxia and/or spastic paraplegia in consanguineous families. This study aims to clarify the genetic spectrum of patients with autosomal recessive hereditary ataxia and spastic paraplegias (AR-HA/HSPs) in consanguineous families. METHODS: A total of 36 AR-HA/HSPs consanguineous pedigrees from China were recruited into this study. Next generation sequencing (NGS), guided by homozygosity mapping (HM), was applied to identify the pathogenic variants in known genes or novel candidate genes. RESULTS: We totally made molecular diagnosis in 47.2% (17/36) of AR-HA/HSPs families. Among them, 13 AR-HAs carried pathogenic variants in SETX (n = 4), SACS (n = 2), STUB1, HSD17B4, NEU1, ADCK3, TPP1, PLA2G6 and MTCL1, while four AR-HSPs carried pathogenic variants in SPG11, ZFYVE26, ATP13A2 and ABCD1. One homozygous nonsense mutation in MRPS27 was identified in an AR-HA family, which was potentially a novel candidate gene of AR-HA. CONCLUSION: HM and NGS can serve as an efficient molecular diagnostic tool for AR-HA/HSPs in consanguineous families. Our findings provide a better understanding of genetic architecture of AR-HA/HSPs in consanguinity and broaden the clinical-genetic spectrum of the disease.

13.
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
14.
Transl Res ; 223: 15-24, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32434004

RESUMO

Smad4 plays a central role in the regulation of extracellular matrix (ECM) protein expression and cell differentiation; however, the molecular regulation of Smad4 protein stability by a deubiquitinase has not been reported. In the current study, we reveal that a deubiquitinase USP13 stabilizes Smad4, ultimately modulating ECM protein expression in lung fibroblast cells. USP13 was increased in primary adult lung fibroblasts isolated from bleomycin-challenged mice and transforming growth factor (TGF)-ß1-treated primary mouse lung fibroblasts. In a bleomycin-induced murine model of lung fibrosis, USP13-deficient mice showed reduced ECM levels such as fibronectin (FN) and collagen compared with wild-type mice. The reductions in both protein levels and mRNA expression of ECM were observed in the isolated lung fibroblasts from USP13-deficient mice, suggesting that downregulation of USP13 reduces ECM levels through inhibiting its transcription. To investigate the molecular mechanisms by which USP13 modulates ECM expression, we focused on the role of USP13 on Smad4 expression. Overexpression of USP13 increased FN and Smad4 protein levels in lung fibroblasts, while downregulation of USP13 reduced Smad4 protein levels, without altering Smad4 mRNA expression, suggesting that USP13 regulates Smad4 protein stability. Knockdown of USP13 decreased Smad4 half-life and promoted Smad4 ubiquitination. Both Smad4 and USP13 were co-localized in the cytoplasm in treated cell, and co-translocated into the nucleus in response to TGF-ß1. The results indicate that USP13 promotes ECM expression by stabilizing Smad4 in lung fibroblasts and plays a role in the maintenance of the extracellular matrix in lungs.


Assuntos
Enzimas Desubiquitinantes/metabolismo , Matriz Extracelular/metabolismo , Fibroblastos/metabolismo , Pulmão/citologia , Proteína Smad4/metabolismo , Animais , Bleomicina , Regulação para Baixo , Fibronectinas/metabolismo , Camundongos Endogâmicos C57BL , Poliubiquitina/metabolismo , Estabilidade Proteica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteína Smad4/genética , Fator de Crescimento Transformador beta1 , Ubiquitinação
15.
JCI Insight ; 5(4)2020 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-32102983

RESUMO

Accumulation of amyloid ß protein (Aß) due to increased generation and/or impaired degradation plays an important role in Alzheimer's disease (AD) pathogenesis. In this report, we describe the identification of rare coding mutations in the endothelin-converting enzyme 2 (ECE2) gene in 1 late-onset AD family, and additional case-control cohort analysis indicates ECE2 variants associated with the risk of developing AD. The 2 mutations (R186C and F751S) located in the peptidase domain in the ECE2 protein were found to severely impair the enzymatic activity of ECE2 in Aß degradation. We further evaluated the effect of the R186C mutation in mutant APP-knockin mice. Overexpression of wild-type ECE2 in the hippocampus reduced amyloid load and plaque formation, and improved learning and memory deficits in the AD model mice. However, the effect was abolished by the R186C mutation in ECE2. Taken together, the results demonstrated that ECE2 peptidase mutations contribute to AD pathogenesis by impairing Aß degradation, and overexpression of ECE2 alleviates AD phenotypes. This study indicates that ECE2 is a risk gene for AD development and pharmacological activation of ECE2 could be a promising strategy for AD treatment.


Assuntos
Doença de Alzheimer/genética , Encéfalo/metabolismo , Enzimas Conversoras de Endotelina/genética , Doença de Alzheimer/diagnóstico por imagem , Animais , Encéfalo/diagnóstico por imagem , Estudos de Casos e Controles , Estudos de Coortes , Modelos Animais de Doenças , Enzimas Conversoras de Endotelina/metabolismo , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Camundongos , Mutação , Linhagem
16.
Neurobiol Aging ; 89: 142.e1-142.e7, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32081467

RESUMO

Recently, the (GGC)n repeat expansion in the NOTCH2NLC gene has been identified to be associated with neuronal intranuclear inclusion disease (NIID). Given the clinical overlap of dementia-dominant NIID with neurodegenerative dementia, we therefore hypothesized that the NOTCH2NLC repeat expansion might also contribute to these diseases. In the present study, repeat primed polymerase chain reaction (RP-PCR) and GC-rich PCR were conducted to detect the repeats of NOTCH2NLC in a cohort of 1004 patients with neurodegenerative dementias from mainland China. As a result, 4 sporadic patients were found to carry the NOTCH2NLC repeats expansion, totally accounting for 0.4% of all dementia individuals, and the accurate repeated sizes were 110, 133,120 and 76 respectively. Of 4 mutation carriers, three and one were clinically diagnosed Alzheimer's disease (AD) and frontotemporal dementia (FTD) respectively. In addition, 3 out of them revealed leukoencephalopathy in T2-Flair imaging. This study revealed that although rare, the NOTCH2NLC repeat expansions may be associated with AD or FTD-like phenotype as well as leukoencephalopathy.


Assuntos
Doença de Alzheimer/genética , Expansão das Repetições de DNA , Demência Frontotemporal/genética , Leucoencefalopatias/genética , Doenças Neurodegenerativas/genética , Receptor Notch2/genética , Idoso , China , Estudos de Coortes , Feminino , Estudos de Associação Genética , Humanos , Corpos de Inclusão Intranuclear/genética , Masculino , Pessoa de Meia-Idade
17.
J Clin Neurosci ; 73: 311-313, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31987637

RESUMO

Charcot-Marie-Tooth (CMT) disease is the most common hereditary peripheral neuropathy. X-linked Charcot-Marie-Tooth disease in the GJB1 gene is known as CMTX1. We report a 14 years-old young man with walked unstably, bilateral strephenopodia, severe alopecia and paroxysmal bilateral upper limbs tremor without obvious muscle atrophy. Diagnostic whole-exome sequencing revealed a hemizygote missense mutation c.278 T > A in exon 2 of the GJB1 gene, with lysine at position 93 of the mature protein (p.M93K). This is the first CMT case with alopecia areata reported in the world.


Assuntos
Doença de Charcot-Marie-Tooth/diagnóstico , Conexinas/genética , Fenótipo , Adolescente , Doença de Charcot-Marie-Tooth/genética , Testes Genéticos , Humanos , Masculino , Mutação de Sentido Incorreto , Sequenciamento Completo do Exoma
18.
J Hepatol ; 72(3): 420-430, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31610223

RESUMO

BACKGROUND & AIMS: Although CD8+T cell exhaustion hampers viral control during chronic HBV infection, the pool of CD8+T cells is phenotypically and functionally heterogeneous. Therefore, a specific subpopulation of CD8+T cells should be further investigated. This study aims to dissect a subset of CD8+T cells expressing C-X-C motif chemokine receptor 5 (CXCR5) in chronic HBV infection. METHODS: The frequency of CXCR5+CD8+T cells and the levels of C-X-C motif chemokine ligand 13 (CXCL13), a chemokine of CXCR5, were measured in patients with chronic HBV infection. C57BL/6, interleukin (IL)-21 receptor- or B cell-deficient mice were hydrodynamically injected with pAAV-HBV1.2 plasmids. Phenotype and functions of peripheral and intrahepatic CXCR5+ and CXCR5-CD8+T cells were assessed. RESULTS: CXCR5+CD8+T cells were partially exhausted but possessed a stronger antiviral ability than the CXCR5- subset in patients with chronic HBV infection; moreover, CXCR5+CD8+T cells were associated with a favorable treatment response in patients with chronic hepatitis B (CHB). High levels of CXCL13 from patients with CHB facilitated the recruitment of intrahepatic CXCR5+CD8+T cells, and this subpopulation produced high levels of HBV-specific interferon (IFN)-γ and IL-21. Notably, PD1 (programmed death 1) blockade and exogenous IL-21 enhanced the production of IFN-γ. More strikingly, mice injected with CXCR5+CD8+T cells showed remarkably decreased expression of HBsAg. Additionally, an impaired production of HBV-specific IFN-γ from intrahepatic CXCR5+CD8+T cells was observed in IL-21 receptor- or B cell-deficient mice. CONCLUSION: CXCL13 promotes the recruitment of CXCR5+CD8+T cells to the liver, and this subpopulation improves viral control in chronic HBV infection. The identification of this unique subpopulation may contribute to a better understanding of CD8+T cell functions and provide a potential immunotherapeutic target in chronic HBV infection. LAY SUMMARY: Exhaustion of CD8+ T cells is an important factor in the development of chronic hepatitis B virus (HBV) infection. CD8+ T cells expressing the receptor CXCR5 are partially exhausted, but have potent antiviral activity, as they produce high levels of HBV-specific cytokines in chronic HBV infection. Increased expression of CXCL13 within the liver facilitates the recruitment of CXCR5+CD8+T cells and establishes effective immune control of HBV infection.

19.
Ultrasonics ; 102: 106040, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31678642

RESUMO

A ring-shaped traveling wave ultrasonic motor with a suspension stator is proposed for improving output power density. Piezoelectric stacks working in d33 mode are involved in the stator, whereas piezoelectric plates employed in classic ring-shaped traveling wave motors often work in d31 mode. Spring-mass systems are used to suspend the stator from the base that supports the motor and provide preload force. The volume of piezoelectric material and the power density of the motor can be easily increased through the suspension structure. Large vibration amplitude of the stator can be generated on the coupling surface. Simulink analysis and finite element analysis are conducted to verify the theory and determine the optimum parameters of the suspension stator with four piezoelectric stacks. The maximum free vibration amplitude of 4.25 µm of the stator is observed, which is nearly 4.7 times of that without suspension. The prototype can work at a maximum no-load speed of 62 rpm and produce a stall torque of 49.5 mN m under a driving signal of 30 Vpp when the mass block is 0.30 g. Furthermore, the higher output power can be expected because more extra stacks can be added in this suspension structure.

20.
J Alzheimers Dis ; 72(2): 633-640, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31594229

RESUMO

Recent studies found that poor oral hygiene was associated with increased risk of dementia, and the number of oral bacteria significantly increased in the brain tissues of patients with Alzheimer's disease (AD), suggesting that the oral microbiota may play an important role in the pathogenesis of AD. However, the actual composition of oral bacteria communities in patients with AD and whether these oral bacteria are associated with disease severity remain largely unknown. Also, the APOEɛ4 polymorphism is a strong risk factor for sporadic AD, and it would be pertinent to see if the bacterial flora was different in those patients who were APOEɛ4 positive. A total of 78 subjects were recruited in this study, including 39 patients with AD and 39 healthy controls. Saliva was collected from each subject. 16S ribosomal RNA (16S rRNA) sequencing was conducted to analyze the salivary microbiota, and Sanger sequencing was performed to analyze the APOE genotype. There was a significantly lower richness and diversity of saliva microbiota detected in AD patients than healthy controls. The relative abundance of Moraxella, Leptotrichia, and Sphaerochaeta in the saliva of AD patients greatly increased, whereas that of Rothia was significantly reduced. Compared with APOEɛ4 (-) patients, the level of Abiotrophia and Desulfomicrobium was comparatively abundant, while Actinobacillus and Actinomyces decreased significantly in patients carrying the APOEɛ4. No bacteria were found to be associated with the severity of AD. This is the first study to analyze the salivary microorganisms in patients with AD, and we discovered that the composition of salivary microbiome was altered in AD, providing further support for the role of the oral microbiome in AD development.


Assuntos
Doença de Alzheimer/microbiologia , Microbiota , Saliva/microbiologia , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/genética , Doença de Alzheimer/psicologia , Apolipoproteína E4/genética , DNA/química , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , RNA Ribossômico 16S/análise
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...