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1.
Comput Biol Med ; 168: 107753, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38039889

RESUMO

BACKGROUND: Trans-acting factors are of special importance in transcription regulation, which is a group of proteins that can directly or indirectly recognize or bind to the 8-12 bp core sequence of cis-acting elements and regulate the transcription efficiency of target genes. The progressive development in high-throughput chromatin capture technology (e.g., Hi-C) enables the identification of chromatin-interacting sequence groups where trans-acting DNA motif groups can be discovered. The problem difficulty lies in the combinatorial nature of DNA sequence pattern matching and its underlying sequence pattern search space. METHOD: Here, we propose to develop MotifHub for trans-acting DNA motif group discovery on grouped sequences. Specifically, the main approach is to develop probabilistic modeling for accommodating the stochastic nature of DNA motif patterns. RESULTS: Based on the modeling, we develop global sampling techniques based on EM and Gibbs sampling to address the global optimization challenge for model fitting with latent variables. The results reflect that our proposed approaches demonstrate promising performance with linear time complexities. CONCLUSION: MotifHub is a novel algorithm considering the identification of both DNA co-binding motif groups and trans-acting TFs. Our study paves the way for identifying hub TFs of stem cell development (OCT4 and SOX2) and determining potential therapeutic targets of prostate cancer (FOXA1 and MYC). To ensure scientific reproducibility and long-term impact, its matrix-algebra-optimized source code is released at http://bioinfo.cs.cityu.edu.hk/MotifHub.


Assuntos
Algoritmos , Software , Motivos de Nucleotídeos/genética , Reprodutibilidade dos Testes , Cromatina/genética
2.
Nanotechnology ; 35(13)2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38055996

RESUMO

Advances in mobile electronics and telecommunication systems along with 5G technologies have been escalating the electromagnetic interference (EMI) problem in recent years. Graphene-based material systems such as pristine graphene, graphene-polymer composites and other graphene-containing candidates have been shown to provide adequate EMI shielding performance. Besides achieving the needed shielding effectiveness (SE), the method of applying the candidate shielding material onto the object in need of protection is of enormous importance due to considerations of ease of application, reduced logistics and infrastructure, rapid prototyping and throughput, versatility to handle both rigid and flexible substrates and cost. Printing readily meets all these criteria and here we demonstrate plasma jet printing of thin films of graphene and its composite with copper to meet the EMI shielding needs. SE over 30 dB is achieved, which represents blocking over 99.9% of the incoming radiation. Graphene and its composite with copper yield higher green index compared to pure copper shields, implying reduced reflection of incoming electromagnetic waves to help reduce secondary pollution.

3.
Nat Aging ; 3(10): 1219-1236, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37735240

RESUMO

In Alzheimer's disease (AD), sensome receptor dysfunction impairs microglial danger-associated molecular pattern (DAMP) clearance and exacerbates disease pathology. Although extrinsic signals, including interleukin-33 (IL-33), can restore microglial DAMP clearance, it remains largely unclear how the sensome receptor is regulated and interacts with DAMP during phagocytic clearance. Here, we show that IL-33 induces VCAM1 in microglia, which promotes microglial chemotaxis toward amyloid-beta (Aß) plaque-associated ApoE, and leads to Aß clearance. We show that IL-33 stimulates a chemotactic state in microglia, characterized by Aß-directed migration. Functional screening identified that VCAM1 directs microglial Aß chemotaxis by sensing Aß plaque-associated ApoE. Moreover, we found that disrupting VCAM1-ApoE interaction abolishes microglial Aß chemotaxis, resulting in decreased microglial clearance of Aß. In patients with AD, higher cerebrospinal fluid levels of soluble VCAM1 were correlated with impaired microglial Aß chemotaxis. Together, our findings demonstrate that promoting VCAM1-ApoE-dependent microglial functions ameliorates AD pathology.


Assuntos
Doença de Alzheimer , Humanos , Doença de Alzheimer/genética , Microglia/metabolismo , Interleucina-33/metabolismo , Quimiotaxia , Peptídeos beta-Amiloides/metabolismo , Apolipoproteínas E/metabolismo
5.
Hear Res ; 431: 108740, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36948126

RESUMO

To process sensory stimuli, intense energy demands are placed on hair cells and primary afferents. Hair cells must both mechanotransduce and maintain pools of synaptic vesicles for neurotransmission. Furthermore, both hair cells and afferent neurons must continually maintain a polarized membrane to propagate sensory information. These processes are energy demanding and therefore both cell types are critically reliant on mitochondrial health and function for their activity and maintenance. Based on these demands, it is not surprising that deficits in mitochondrial health can negatively impact the auditory and vestibular systems. In this review, we reflect on how mitochondrial function and dysfunction are implicated in hair cell-mediated sensory system biology. Specifically, we focus on live imaging approaches that have been applied to study mitochondria using the zebrafish lateral-line system. We highlight the fluorescent dyes and genetically encoded biosensors that have been used to study mitochondria in lateral-line hair cells and afferent neurons. We then describe the impact this in vivo work has had on the field of mitochondrial biology as well as the relationship between mitochondria and sensory system development, function, and survival. Finally, we delineate the areas in need of further exploration. This includes in vivo analyses of mitochondrial dynamics and biogenesis, which will round out our understanding of mitochondrial biology in this sensitive sensory system.


Assuntos
Sistema da Linha Lateral , Mitocôndrias , Neurônios , Sistema da Linha Lateral/citologia , Sistema da Linha Lateral/fisiologia , Animais , Peixe-Zebra , Neurônios/citologia , Sistema Vestibular/citologia , Sistema Vestibular/fisiologia , Técnicas Biossensoriais
6.
Muscle Nerve ; 67(4): 259-271, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36448457

RESUMO

Small-fiber neuropathy (SFN) is a disorder that exclusively affects the small nerve fibers, sparing the large nerve fibers. Thinly myelinated Aδ-fibers and unmyelinated C-fibers are damaged, leading to development of neuropathic pain, thermal dysfunction, sensory symptoms, and autonomic disturbances. Although many SFNs are secondary and due to immunological causes or metabolic disturbances, the etiology is unknown in up to half of the patients. Over the years, this proportion of "idiopathic SFN" has decreased, as familial and genetic causes have been discovered, thus shifting a proportion of once "idiopathic" cases to the genetic category. After the discovery of SCN9A-gene variants in 2012, SCN10A and SCN11A variants have been found to be pathogenic in SFN. With improved accessibility of SFN diagnostic tools and genetic tests, many non-SCN variants and genetically inherited systemic diseases involving the small nerve fibers have also been described, but only scattered throughout the literature. There are 80 SCN variants described as causing SFN, 8 genes causing hereditary sensory autonomic neuropathies (HSAN) described with pure SFN, and at least 7 genes involved in genetically inherited systemic diseases associated with SFN. This systematic review aims to consolidate and provide an updated overview on the genetic variants of SFN to date---SCN genes and beyond. Awareness of these genetic causes of SFN is imperative for providing treatment directions, prognostication, and management of expectations for patients and their health-care providers.


Assuntos
Neuralgia , Neuropatia de Pequenas Fibras , Humanos , Neuropatia de Pequenas Fibras/patologia , Neuralgia/etiologia , Fibras Nervosas Amielínicas/patologia , Testes Genéticos , Causalidade , Canal de Sódio Disparado por Voltagem NAV1.7/genética
7.
Autophagy ; 19(5): 1406-1423, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36130166

RESUMO

Macroautophagy/autophagy, an evolutionarily conserved degradative process essential for cell homeostasis and development in eukaryotes, involves autophagosome formation and fusion with a lysosome/vacuole. The soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) proteins play important roles in regulating autophagy in mammals and yeast, but relatively little is known about SNARE function in plant autophagy. Here we identified and characterized two Arabidopsis SNAREs, AT4G15780/VAMP724 and AT1G04760/VAMP726, involved in plant autophagy. Phenotypic analysis showed that mutants of VAMP724 and VAMP726 are sensitive to nutrient-starved conditions. Live-cell imaging on mutants of VAMP724 and VAMP726 expressing YFP-ATG8e showed the formation of abnormal autophagic structures outside the vacuoles and compromised autophagic flux. Further immunogold transmission electron microscopy and electron tomography (ET) analysis demonstrated a direct connection between the tubular autophagic structures and the endoplasmic reticulum (ER) in vamp724-1 vamp726-1 double mutants. Further transient co-expression, co-immunoprecipitation and double immunogold TEM analysis showed that ATG9 (autophagy related 9) interacts and colocalizes with VAMP724 and VAMP726 in ATG9-positive vesicles during autophagosome formation. Taken together, VAMP724 and VAMP726 regulate autophagosome formation likely working together with ATG9 in Arabidopsis.Abbreviations: ATG, autophagy related; BTH, benzo-(1,2,3)-thiadiazole-7-carbothioic acid S-methyl ester; Conc A, concanamycin A; EM, electron microscopy; ER, endoplasmic reticulum; FRET, Förster/fluorescence resonance energy transfer; MS, Murashige and Skoog; MVB, multivesicular body; PAS, phagophore assembly site; PM, plasma membrane; PVC, prevacuolar compartment; SNARE, soluble N-ethylmaleimide-sensitive factor attachment protein receptor; TEM, transmission electron microscopy; TGN, trans-Golgi network; WT, wild-type.


Assuntos
Arabidopsis , Proteínas de Saccharomyces cerevisiae , Animais , Arabidopsis/genética , Arabidopsis/metabolismo , Autofagossomos/metabolismo , Autofagia/fisiologia , Macroautofagia , Proteínas de Ligação a Fator Solúvel Sensível a N-Etilmaleimida/metabolismo , Saccharomyces cerevisiae/metabolismo , Endossomos/metabolismo , Proteínas SNARE/metabolismo , Proteínas Relacionadas à Autofagia/metabolismo , Mamíferos/metabolismo , Proteínas de Membrana/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo
8.
STAR Protoc ; 3(4): 101766, 2022 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-36240058

RESUMO

In this protocol, we describe steps that utilize the optical clarity of the zebrafish larvae and the stereotyped motor neuron axon structure in the trunk to measure spontaneous or evoked motor neuron axon activity. This activity is detected with transgenic fluorescent indicators introduced into the larvae by zygotic injection. Fluorescent indicator intensity changes in the small neuromuscular junctions are quantified to measure the presynaptic calcium activity and consequent synaptic vesicle release. For complete details on the use and execution of this protocol, please refer to Mandal et al. (2020).


Assuntos
Neurônios Motores , Peixe-Zebra , Animais , Junção Neuromuscular/fisiologia , Axônios/fisiologia , Vesículas Sinápticas/fisiologia , Animais Geneticamente Modificados
9.
J Assoc Res Otolaryngol ; 23(6): 683-700, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36261670

RESUMO

The synthetic glucocorticoid dexamethasone is commonly used to treat inner ear disorders. Previous work in larval zebrafish has shown that dexamethasone treatment enhances hair cell regeneration, yet dexamethasone has also been shown to inhibit regeneration of peripheral nerves after lesion. We therefore used the zebrafish model to determine the impact of dexamethasone treatment on lateral-line hair cells and primary afferents. To explore dexamethasone in the context of regeneration, we used copper sulfate (CuSO4) to induce hair cell loss and retraction of nerve terminals, and then allowed animals to recover in dexamethasone for 48 h. Consistent with previous work, we observed significantly more regenerated hair cells in dexamethasone-treated larvae. Importantly, we found that the afferent processes beneath neuromasts also regenerated in the presence of dexamethasone and formed an appropriate number of synapses, indicating that innervation of hair cells was not inhibited by dexamethasone. In addition to regeneration, we also explored the effects of prolonged dexamethasone exposure on lateral-line homeostasis and function. Following dexamethasone treatment, we observed hyperpolarized mitochondrial membrane potentials (ΔΨm) in neuromast hair cells and supporting cells. Hair cells exposed to dexamethasone were also more vulnerable to neomycin-induced cell death. In response to a fluid-jet delivered saturating stimulus, calcium influx through hair cell mechanotransduction channels was significantly reduced, yet presynaptic calcium influx was unchanged. Cumulatively, these observations indicate that dexamethasone enhances hair cell regeneration in lateral-line neuromasts, yet also disrupts mitochondrial homeostasis, making hair cells more vulnerable to ototoxic insults and possibly impacting hair cell function.


Assuntos
Sistema da Linha Lateral , Peixe-Zebra , Animais , Peixe-Zebra/fisiologia , Mecanotransdução Celular , Cálcio/metabolismo , Cálcio/farmacologia , Cabelo , Dexametasona/toxicidade , Dexametasona/metabolismo , Sistema da Linha Lateral/fisiologia
10.
Life (Basel) ; 12(9)2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-36143416

RESUMO

Background: Traditionally, cancer prognosis was determined by tumours size, lymph node spread and presence of metastasis (TNM staging). Radiomics of tumour volume has recently been used for prognosis prediction. In the present study, we evaluated the effect of various sizes of tumour volume. A voted ensemble approach with a combination of multiple machine learning algorithms is proposed for prognosis prediction for head and neck squamous cell carcinoma (HNSCC). Methods: A total of 215 HNSCC CT image sets with radiotherapy structure sets were acquired from The Cancer Imaging Archive (TCIA). Six tumour volumes, including gross tumour volume (GTV), diminished GTV, extended GTV, planning target volume (PTV), diminished PTV and extended PTV were delineated. The extracted radiomics features were analysed by decision tree, random forest, extreme boost, support vector machine and generalized linear algorithms. A voted ensemble machine learning (VEML) model that optimizes the above algorithms was used. The receiver operating characteristic area under the curve (ROC-AUC) were used to compare the performance of machine learning methods, including accuracy, sensitivity and specificity. Results: The VEML model demonstrated good prognosis prediction ability for all sizes of tumour volumes with reference to GTV and PTV with high accuracy of up to 88.3%, sensitivity of up to 79.9% and specificity of up to 96.6%. There was no significant difference between the various target volumes for the prognostic prediction of HNSCC patients (chi-square test, p > 0.05). Conclusions: Our study demonstrates that the proposed VEML model can accurately predict the prognosis of HNSCC patients using radiomics features from various tumour volumes.

11.
Osteoporos Int ; 33(12): 2453-2466, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35776148

RESUMO

The overall incidence of imminent fracture after a prior fragility fracture was 7.58% in the first year and 11.58% in the first 2 years. Approximately half of re-fractures occurred in the first 2 years after a fragility fracture. Older patients that have suffered from a fragility fracture should be treated promptly, with immediate care and a secondary fracture prevention to prevent the high imminent risk of a fracture. INTRODUCTION: Imminent fractures refer to the fractures that occur within 2 years of an initial fracture. It is well known that the risk of a subsequent fracture is not constant with time and occurs shortly after the initial one. This systematic review and meta-analysis aimed to present the existing data on imminent fracture worldwide. METHODS: Literature search was conducted in Pubmed, Embase, and Web of Science databases until 26 October 2021 for studies reporting the incidence of imminent osteoporotic fractures among people aged 50 years or older. The overall incidence of imminent fracture was pooled and subgroup analyses of index fracture sites and regions on incidence of imminent fracture were performed, with the 95% confidence interval (CI) being calculated. Percentage of imminent fracture occurring in follow-up period was calculated and pooled by meta-analysis. Hazard ratio (HR) was used to estimate the gender differences on the imminent risk of fracture. RESULTS: A total of 1446 articles were identified. Nineteen observational studies were eligible for our systematic review, in which 18 were used for quantitative analysis. Pooled overall incidence of imminent fracture in the first year after an osteoporotic fracture was 7.58% (95% CI 5.84 to 9.31%) and cumulative incidence in the first 2 years was 11.58% (95% CI 8.94 to 14.21%). Subgroup analysis showed that in the first 2 years, the pooled incidence in Asia was 7.30% (95% CI 3.42 to 11.18%), whilst incidence in Europe/North America was 13.17% (95% CI 10.14 to 16.20%). In included studies with follow-up period of more than 5 years, pooled imminent fracture percentage in the first 2 years was 47.24% (95% CI 26.18 to 68.30%). Hazard ratio (HR) on gender showed that women had an overall slight increase in risk of imminent fractures (HR 1.18, 95% CI 1.11 to 1.25). CONCLUSION: The incidence of imminent fracture is high globally at 11.58%. Approximately half of all refractures occur in the first 2 years after an index fragility fracture. Older patients that have suffered from a fragility fracture should be treated promptly. Also, immediate care and secondary fracture prevention are necessary to prevent the high imminent risk of a fracture, especially within the first 2 years.


Assuntos
Fraturas por Osteoporose , Humanos , Feminino , Fraturas por Osteoporose/epidemiologia , Fraturas por Osteoporose/etiologia , Fraturas por Osteoporose/prevenção & controle , Incidência , Bases de Dados Factuais , Europa (Continente) , Ásia , Estudos Observacionais como Assunto
12.
J Alzheimers Dis ; 87(3): 1205-1213, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35466936

RESUMO

BACKGROUND: Alzheimer's disease (AD) is the most common cause of dementia in the elderly population. However, epidemiological studies on the demographics of AD in Hong Kong population are lacking. OBJECTIVE: We investigated the demographics, comorbidities, mortality rates, and medication use of patients with AD in Hong Kong to understand how the disease has been managed locally. METHODS: This was a collaborative study of The Hong Kong University of Science and Technology and the Hospital Authority Data Collaboration Lab. We analyzed the demographic data, clinical records, diagnoses, and medication records of patients with AD under the care of the Hospital Authority between January 1, 2007 and December 31, 2017. RESULTS: We identified 23,467 patients diagnosed with AD. The median age at diagnosis was 84 years old, and 71% of patients were female. The most common comorbidity was hypertension (52.6%). 39.9% of patients received medications for dementia; of those, 68.4% had taken those medications for > 1 year. Compared to nonusers, long-term AD medication users had a significantly younger age of AD onset and were taking more lipid-regulating medication, diabetes medication, or antidepressants. Surprisingly, the use of antipsychotics in patients with AD was quite common; 50.7% of patients had received any type of antipsychotic during disease progression. CONCLUSION: This study provides detailed information on the demographics and medication use of patients with AD in Hong Kong. The data from this AD cohort will aid our future research aiming to identify potential AD risk factors and associations between AD and other diseases.


Assuntos
Doença de Alzheimer , Antipsicóticos , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/epidemiologia , Antipsicóticos/uso terapêutico , Estudos de Coortes , Demografia , Feminino , Hong Kong/epidemiologia , Humanos , Masculino
13.
World J Clin Cases ; 10(6): 1896-1902, 2022 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-35317159

RESUMO

BACKGROUND: Guillain-Barré syndrome (GBS) is an autoimmune-mediated peripheral neuropathy characterized by symmetric weakness. Asymmetric weakness in GBS is uncommon and may be easily confused with other differential diagnoses. We herein present three cases of asymmetric GBS and review the literature on this atypical subtype of GBS in order to describe the characteristics of asymmetric GBS and to provide experience for clinicians. CASE SUMMARY: Different from patients in the previous reports, our patients showed persistent asymmetric limb weakness from the onset to recovery phase. All three patients were serologically positive for antecedent infections. Two of the three cases had IgG antibodies against ganglioside GM1. Two patients received immunotherapy including intravenous immunoglobulin and plasma exchange, while one patient received only supportive treatment. Autoantibodies against gangliosides, asymmetry of congenital development of blood-nerve barrier and limb use may contribute to the development of asymmetric limb weakness in GBS. CONCLUSION: Asymmetric GBS may be a rare clinical variant and should be considered when a patient develops acute and progressive asymmetric limb weakness. The differences in clinical features and prognosis between asymmetric GBS and classic GBS deserve further investigation in a large study.

14.
Cancer Immunol Immunother ; 71(11): 2583-2596, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35299256

RESUMO

Non-keratinizing nasopharyngeal carcinoma (NPC) is a malignancy with a poor prognosis for relapsing patients and those with metastatic disease. Here, we identify a novel disease mechanism of NPC which may be its Achilles' heel that makes it susceptible to immunotherapy. CD137 is a potent costimulatory receptor on activated T cells, and CD137 agonists strongly enhance anti-tumor immune responses. A negative feedback mechanism prevents overstimulation by transferring CD137 from T cells to CD137 ligand (CD137L)-expressing antigen presenting cells (APC) during cognate interaction, upon which the CD137-CD137L complex is internalized and degraded. We found ectopic expression of CD137 on 42 of 122 (34.4%) NPC cases, and that CD137 is induced by the Epstein-Barr virus latent membrane protein (LMP) 1. CD137 expression enables NPC to hijack the inbuilt negative feedback mechanism to downregulate the costimulatory CD137L on APC, facilitating its escape from immune surveillance. Further, the ectopically expressed CD137 signals into NPC cells via the p38-MAPK pathway, and induces the expression of IL-6, IL-8 and Laminin γ2. As much as ectopic CD137 expression may support the growth and spread of NPC, it may be a target for its immunotherapeutic elimination. Natural killer cells that express a CD137-specific chimeric antigen receptor induce death in CD137+ NPC cells, in vitro, and in vivo in a murine xenograft model. These data identify a novel immune escape mechanism of NPC, and lay the foundation for an urgently needed immunotherapeutic approach for NPC.


Assuntos
Infecções por Vírus Epstein-Barr , Neoplasias Nasofaríngeas , Receptores de Antígenos Quiméricos , Ligante 4-1BB , Animais , Herpesvirus Humano 4 , Humanos , Interleucina-6 , Interleucina-8 , Laminina , Camundongos , Carcinoma Nasofaríngeo , Recidiva Local de Neoplasia , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral
15.
Proc Natl Acad Sci U S A ; 119(1)2022 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-34983843

RESUMO

In Arabidopsis, vacuolar sorting receptor isoform 1 (VSR1) sorts 12S globulins to the protein storage vacuoles during seed development. Vacuolar sorting is mediated by specific protein-protein interactions between VSR1 and the vacuolar sorting determinant located at the C terminus (ctVSD) on the cargo proteins. Here, we determined the crystal structure of the protease-associated domain of VSR1 (VSR1-PA) in complex with the C-terminal pentapeptide (468RVAAA472) of cruciferin 1, an isoform of 12S globulins. The 468RVA470 motif forms a parallel ß-sheet with the switch III residues (127TMD129) of VSR1-PA, and the 471AA472 motif docks to a cradle formed by the cargo-binding loop (95RGDCYF100), making a hydrophobic interaction with Tyr99. The C-terminal carboxyl group of the ctVSD is recognized by forming salt bridges with Arg95. The C-terminal sequences of cruciferin 1 and vicilin-like storage protein 22 were sufficient to redirect the secretory red fluorescent protein (spRFP) to the vacuoles in Arabidopsis protoplasts. Adding a proline residue to the C terminus of the ctVSD and R95M substitution of VSR1 disrupted receptor-cargo interactions in vitro and led to increased secretion of spRFP in Arabidopsis protoplasts. How VSR1-PA recognizes ctVSDs of other storage proteins was modeled. The last three residues of ctVSD prefer hydrophobic residues because they form a hydrophobic cluster with Tyr99 of VSR1-PA. Due to charge-charge interactions, conserved acidic residues, Asp129 and Glu132, around the cargo-binding site should prefer basic residues over acidic ones in the ctVSD. The structural insights gained may be useful in targeting recombinant proteins to the protein storage vacuoles in seeds.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Substituição de Aminoácidos , Arabidopsis/química , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Cristalografia por Raios X , Mutação de Sentido Incorreto , Conformação Proteica em Folha beta , Domínios Proteicos , Transporte Proteico , Protoplastos/química , Protoplastos/metabolismo , Proteínas de Armazenamento de Sementes/química , Proteínas de Armazenamento de Sementes/genética , Proteínas de Armazenamento de Sementes/metabolismo , Relação Estrutura-Atividade , Vacúolos/química , Vacúolos/genética , Vacúolos/metabolismo
16.
Ann Neurol ; 91(1): 66-77, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34761434

RESUMO

OBJECTIVE: Small fiber neuropathy (SFN) is clinically and etiologically heterogeneous. Although autoimmunity has been postulated to be pathophysiologically important in SFN, few autoantibodies have been described. We aimed to identify autoantibodies associated with idiopathic SFN (iSFN) by a novel high-throughput protein microarray platform that captures autoantibodies expressed in the native conformational state. METHODS: Sera from 58 SFN patients and 20 age- and gender-matched healthy controls (HCs) were screened against >1,600 immune-related antigens. Fluorescent unit readout and postassay imaging were performed, followed by composite data normalization and protein fold change (pFC) analysis. Analysis of an independent validation cohort of 33 SFN patients against the same 20 HCs was conducted to identify reproducible proteins in both cohorts. RESULTS: Nine autoantibodies were screened with statistical significance and pFC criteria in both cohorts, with at least 50% change in serum levels. Three proteins showed consistently high fold changes in main and validation cohorts: MX1 (FC = 2.99 and 3.07, respectively, p = 0.003, q = 0.076), DBNL (FC = 2.11 and 2.16, respectively, p = 0.009, q < 0.003), and KRT8 (FC = 1.65 and 1.70, respectively, p = 0.043, q < 0.003). Further subgroup analysis into iSFN and SFN by secondary causes (secondary SFN) in the main cohort showed that MX1 is higher in iSFN compared to secondary SFN (FC = 1.61 vs 0.106, p = 0.009). INTERPRETATION: Novel autoantibodies MX1, DBNL, and KRT8 are found in iSFN. MX1 may allow diagnostic subtyping of iSFN patients. ANN NEUROL 2022;91:66-77.


Assuntos
Autoanticorpos/imunologia , Autoantígenos/imunologia , Neuropatia de Pequenas Fibras/imunologia , Adulto , Idoso , Autoanticorpos/sangue , Estudos de Coortes , Feminino , Humanos , Queratina-8/imunologia , Masculino , Proteínas dos Microfilamentos/imunologia , Pessoa de Meia-Idade , Proteínas de Resistência a Myxovirus/imunologia , Neuropatia de Pequenas Fibras/sangue , Domínios de Homologia de src/imunologia
17.
Nutrition ; 94: 111498, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34911007

RESUMO

OBJECTIVES: The aim of this study was to evaluate the quality of dietary assessment methods in randomized controlled trials focusing on individuals with type 2 diabetes (T2DM), and its impact on the favorability of conclusions. METHODS: MEDLINE, EMBASE, CINAHL, and CENTRAL were searched, from inception until September 2019 for RCTs of dietary interventions in individuals with T2DM. Investigators assessed risk of bias and quality of the dietary measurements using the Cochrane Risk of Bias Assessment Tool 2.0 and the redeveloped EURICA tool, respectively. Random-effects meta-analysis assessed mean changes in hemoglobin (Hb)A1c. The study was conducted in accordance with the Preferred Reporting in Systematic Reviews and Meta-analyses. PROSPERO registration number: CRD42019146471. RESULTS: Of 2552 records retrieved, 23 studies met the inclusion criteria. Two studies were rated as good, 6 as medium, and 15 as poor in the quality assessment of the dietary measurement tool. All eight studies with higher quality of dietary assessment were associated with favorable conclusions. Among the 15 studies with poor quality, 5 failed to draw favorable conclusions. Among studies that sought to produce a reduction in HbA1c, 3 of 6 with better dietary assessment quality produced a significant difference of -0.38% (-0.67% to -0.08%), and 4 of 12 of poorer quality produced a significant difference of -0.26% (-0.37% to -0.14%). CONCLUSIONS: The poor quality of dietary assessment in clinical trials casts uncertainty on the dietary outcomes and the validity of possible causal mechanisms. Attention to the accuracy and reliability of dietary assessment methods is indicated.


Assuntos
Diabetes Mellitus Tipo 2 , Hemoglobinas Glicadas , Humanos , Avaliação Nutricional , Ensaios Clínicos Controlados Aleatórios como Assunto , Reprodutibilidade dos Testes
18.
Nat Aging ; 2(7): 616-634, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-37117777

RESUMO

Changes in the levels of circulating proteins are associated with Alzheimer's disease (AD), whereas their pathogenic roles in AD are unclear. Here, we identified soluble ST2 (sST2), a decoy receptor of interleukin-33-ST2 signaling, as a new disease-causing factor in AD. Increased circulating sST2 level is associated with more severe pathological changes in female individuals with AD. Genome-wide association analysis and CRISPR-Cas9 genome editing identified rs1921622 , a genetic variant in an enhancer element of IL1RL1, which downregulates gene and protein levels of sST2. Mendelian randomization analysis using genetic variants, including rs1921622 , demonstrated that decreased sST2 levels lower AD risk and related endophenotypes in females carrying the Apolipoprotein E (APOE)-ε4 genotype; the association is stronger in Chinese than in European-descent populations. Human and mouse transcriptome and immunohistochemical studies showed that rs1921622 /sST2 regulates amyloid-beta (Aß) pathology through the modulation of microglial activation and Aß clearance. These findings demonstrate how sST2 level is modulated by a genetic variation and plays a disease-causing role in females with AD.


Assuntos
Doença de Alzheimer , Humanos , Feminino , Animais , Camundongos , Doença de Alzheimer/genética , Proteína 1 Semelhante a Receptor de Interleucina-1/genética , Estudo de Associação Genômica Ampla , Apolipoproteína E4/genética , Peptídeos beta-Amiloides/genética
19.
Sci Rep ; 11(1): 14650, 2021 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-34282186

RESUMO

The objective of this study was to investigate the prognostic factors predicting the ambulation recovery of fragility hip fracture patients. 2286 fragility hip fracture patients were collected from the Fragility Fracture Registry in Hong Kong. Predictive factors of ambulation deterioration including age, gender, pre-operation American Society of Anesthesiologists grade, pre-fracture mobility, delay to surgery, length of stay, fracture type, type of surgery, discharge destination and complications were identified. Patients with outdoor unassisted and outdoor with aids ambulatory function before fracture had 3- and 1.5-times increased risk of mobility deterioration, respectively (Odds Ratio (OR) = 2.556 and 1.480, 95% Confidence Interval (CI) 2.101-3.111 and 1.246-1.757, both p < 0.001). Patients living in old age homes had almost 1.4 times increased risk of deterioration when compared to those that lived in their homes (OR = 1.363, 95% CI 1.147-1.619, p < 0.001). The risk also increased for every 10 years of age (OR = 1.831, 95% CI 1.607-2.086, p < 0.001). Patients in the higher risk ASA group shows a decreased risk of ambulation deterioration compared to those in lower risk ASA group (OR = 0.831, 95% CI 0.698-0.988, p = 0.038). Patients who suffered from complications after surgery did not increased risk of mobility decline at 1-year post-surgery. Delayed surgery over 48 h, delayed discharge (> 14 days), early discharge (less than 6 days), and length of stay also did not increased risk of mobility decline. Male patients performed worse in terms of their mobility function after surgery compared to female patients (OR = 1.195, 95% CI 1.070-1.335, p = 0.002). This study identified that better premorbid good function, discharge to old age homes especially newly institutionalized patients, increased age, lower ASA score, and male patients, correlate with mobility deterioration at 1-year post-surgery. With the aging population and development of FLS, prompt identification of at-risk patients should be performed for prevention of deterioration.


Assuntos
Fraturas do Quadril/epidemiologia , Limitação da Mobilidade , Caminhada/estatística & dados numéricos , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Povo Asiático/estatística & dados numéricos , Feminino , Fraturas do Quadril/reabilitação , Hong Kong/epidemiologia , Humanos , Masculino , Prognóstico , Sistema de Registros , Fatores de Risco , Fatores de Tempo , Caminhada/fisiologia
20.
Oncoimmunology ; 10(1): 1877459, 2021 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-33643694

RESUMO

Rhabdomyosarcoma (RMS) is a heterogeneous soft tissue neoplasm most frequently found in children and adolescents. As the prognosis for recurrent and metastatic RMS remains poor, immunotherapies are hoped to improve quality of life and survival. CD137 is a member of tumor necrosis factor receptor family and a T cell costimulatory molecule which induces potent cellular immune responses that are able to eliminate malignant cells. Therefore, it was puzzling to find expression of CD137 on an RMS tissue microarray by multiplex staining. CD137 is not only expressed by infiltrating T cells but also by malignant RMS cells. Functional in vitro experiments demonstrate that CD137 on RMS cells is being transferred to adjacent antigen-presenting cells by trogocytosis, where it downregulates CD137 ligand, and thereby reduces T cell costimulation which results in reduced killing of RMS cells. The transfer of CD137 and the subsequent downregulation of CD137 ligand is a physiological negative feedback mechanism that is likely usurped by RMS, and may facilitate its escape from immune surveillance. In addition, CD137 signals into RMS cells and induces IL-6 and IL-8 secretion, which are linked to RMS metastasis and poor prognosis. However, the ectopic expression of CD137 on RMS cells is an Achilles' heel that may be utilized for immunotherapy. Natural killer cells expressing an anti-CD137 chimeric antigen receptor specifically kill CD137-expressing RMS cells. Our study implicates ectopic CD137 expression as a pathogenesis mechanism in RMS, and it demonstrates that CD137 may be a novel target for immunotherapy of RMS.


Assuntos
Qualidade de Vida , Rabdomiossarcoma , Ligante 4-1BB/genética , Adolescente , Criança , Humanos , Imunoterapia , Rabdomiossarcoma/genética , Linfócitos T , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral
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