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1.
Cell ; 184(25): 6193-6206.e14, 2021 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-34838160

RESUMO

Genetically encoded fluorescent biosensors are powerful tools for monitoring biochemical activities in live cells, but their multiplexing capacity is limited by the available spectral space. We overcome this problem by developing a set of barcoding proteins that can generate over 100 barcodes and are spectrally separable from commonly used biosensors. Mixtures of barcoded cells expressing different biosensors are simultaneously imaged and analyzed by deep learning models to achieve massively multiplexed tracking of signaling events. Importantly, different biosensors in cell mixtures show highly coordinated activities, thus facilitating the delineation of their temporal relationship. Simultaneous tracking of multiple biosensors in the receptor tyrosine kinase signaling network reveals distinct mechanisms of effector adaptation, cell autonomous and non-autonomous effects of KRAS mutations, as well as complex interactions in the network. Biosensor barcoding presents a scalable method to expand multiplexing capabilities for deciphering the complexity of signaling networks and their interactions between cells.


Assuntos
Técnicas Biossensoriais/métodos , Células/ultraestrutura , Microscopia de Fluorescência/métodos , Análise de Célula Única/métodos , Linhagem Celular Tumoral , Humanos
2.
Cell ; 180(6): 1144-1159.e20, 2020 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-32169217

RESUMO

In eukaryotic cells, organelle biogenesis is pivotal for cellular function and cell survival. Chloroplasts are unique organelles with a complex internal membrane network. The mechanisms of the migration of imported nuclear-encoded chloroplast proteins across the crowded stroma to thylakoid membranes are less understood. Here, we identified two Arabidopsis ankyrin-repeat proteins, STT1 and STT2, that specifically mediate sorting of chloroplast twin arginine translocation (cpTat) pathway proteins to thylakoid membranes. STT1 and STT2 form a unique hetero-dimer through interaction of their C-terminal ankyrin domains. Binding of cpTat substrate by N-terminal intrinsically disordered regions of STT complex induces liquid-liquid phase separation. The multivalent nature of STT oligomer is critical for phase separation. STT-Hcf106 interactions reverse phase separation and facilitate cargo targeting and translocation across thylakoid membranes. Thus, the formation of phase-separated droplets emerges as a novel mechanism of intra-chloroplast cargo sorting. Our findings highlight a conserved mechanism of phase separation in regulating organelle biogenesis.


Assuntos
Arabidopsis/metabolismo , Transporte Proteico/fisiologia , Sistema de Translocação de Argininas Geminadas/metabolismo , Proteínas de Cloroplastos/metabolismo , Cloroplastos/metabolismo , Membranas Intracelulares/metabolismo , Proteínas de Membrana/metabolismo , Biogênese de Organelas , Organelas/metabolismo , Transição de Fase , Proteínas de Plantas/metabolismo , Tilacoides/metabolismo , Sistema de Translocação de Argininas Geminadas/fisiologia
3.
Mol Cell ; 70(4): 602-613.e3, 2018 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-29775578

RESUMO

The proteolysis-assisted protein quality control system guards the proteome from potentially detrimental aberrant proteins. How miscellaneous defective proteins are specifically eliminated and which molecular characteristics direct them for removal are fundamental questions. We reveal a mechanism, DesCEND (destruction via C-end degrons), by which CRL2 ubiquitin ligase uses interchangeable substrate receptors to recognize the unusual C termini of abnormal proteins (i.e., C-end degrons). C-end degrons are mostly less than ten residues in length and comprise a few indispensable residues along with some rather degenerate ones. The C-terminal end position is essential for C-end degron function. Truncated selenoproteins generated by translation errors and the USP1 N-terminal fragment from post-translational cleavage are eliminated by DesCEND. DesCEND also targets full-length proteins with naturally occurring C-end degrons. The C-end degron in DesCEND echoes the N-end degron in the N-end rule pathway, highlighting the dominance of protein "ends" as indicators for protein elimination.


Assuntos
Processamento de Proteína Pós-Traducional , Receptores de Citocinas/metabolismo , Selenoproteínas/metabolismo , Proteases Específicas de Ubiquitina/metabolismo , Ubiquitina/metabolismo , Células HEK293 , Células HeLa , Células Hep G2 , Humanos , Domínios Proteicos , Proteólise , Receptores de Citocinas/genética , Proteases Específicas de Ubiquitina/genética
4.
Genes Dev ; 32(17-18): 1161-1174, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-30115631

RESUMO

Alternative splicing (AS) plays important roles in embryonic stem cell (ESC) differentiation. In this study, we first identified transcripts that display specific AS patterns in pluripotent human ESCs (hESCs) relative to differentiated cells. One of these encodes T-cell factor 3 (TCF3), a transcription factor that plays important roles in ESC differentiation. AS creates two TCF3 isoforms, E12 and E47, and we identified two related splicing factors, heterogeneous nuclear ribonucleoproteins (hnRNPs) H1 and F (hnRNP H/F), that regulate TCF3 splicing. We found that hnRNP H/F levels are high in hESCs, leading to high E12 expression, but decrease during differentiation, switching splicing to produce elevated E47 levels. Importantly, hnRNP H/F knockdown not only recapitulated the switch in TCF3 AS but also destabilized hESC colonies and induced differentiation. Providing an explanation for this, we show that expression of known TCF3 target E-cadherin, critical for maintaining ESC pluripotency, is repressed by E47 but not by E12.


Assuntos
Processamento Alternativo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Caderinas/metabolismo , Células-Tronco Embrionárias/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas Grupo F-H/metabolismo , Antígenos CD , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Caderinas/genética , Diferenciação Celular/genética , Linhagem Celular , Células-Tronco Embrionárias/citologia , Éxons , Regulação da Expressão Gênica , Humanos , Precursores de RNA/química , RNA Mensageiro/química , Sequências Reguladoras de Ácido Ribonucleico
5.
EMBO J ; 40(7): e105846, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33469951

RESUMO

Protein termini are determinants of protein stability. Proteins bearing degradation signals, or degrons, at their amino- or carboxyl-termini are eliminated by the N- or C-degron pathways, respectively. We aimed to elucidate the function of C-degron pathways and to unveil how normal proteomes are exempt from C-degron pathway-mediated destruction. Our data reveal that C-degron pathways remove mislocalized cellular proteins and cleavage products of deubiquitinating enzymes. Furthermore, the C-degron and N-degron pathways cooperate in protein removal. Proteome analysis revealed a shortfall in normal proteins targeted by C-degron pathways, but not of defective proteins, suggesting proteolysis-based immunity as a constraint for protein evolution/selection. Our work highlights the importance of protein termini for protein quality surveillance, and the relationship between the functional proteome and protein degradation pathways.


Assuntos
Proteólise , Ubiquitinação , Motivos de Aminoácidos , Linhagem Celular Tumoral , Células HEK293 , Humanos , Transporte Proteico , Proteoma/química , Proteoma/metabolismo , Receptores de Citocinas/metabolismo
6.
J Cell Mol Med ; 28(2): e18031, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37937809

RESUMO

Approximately 10%-15% of couples worldwide are infertile, and male factors account for approximately half of these cases. Teratozoospermia is a major cause of male infertility. Although various mutations have been identified in teratozoospermia, these can vary among ethnic groups. In this study, we performed whole-exome sequencing to identify genetic changes potentially causative of teratozoospermia. Out of seven genes identified, one, ATP/GTP Binding Protein 1 (AGTPBP1), was characterized, and three missense changes were identified in two patients (Affected A: p.Glu423Asp and p.Pro631Leu; Affected B: p.Arg811His). In those two cases, severe sperm head and tail defects were observed. Moreover, AGTPBP1 localization showed a fragmented pattern compared to control participants, with specific localization in the neck and annulus regions. Using murine models, we found that AGTPBP1 is localized in the manchette structure, which is essential for sperm structure formation. Additionally, in Agtpbp1-null mice, we observed sperm head and tail defects similar to those in sperm from AGTPBP1-mutated cases, along with abnormal polyglutamylation tubulin and decreasing △-2 tubulin levels. In this study, we established a link between genetic changes in AGTPBP1 and human teratozoospermia for the first time and identified the role of AGTPBP1 in deglutamination, which is crucial for sperm formation.


Assuntos
Infertilidade Masculina , D-Ala-D-Ala Carboxipeptidase Tipo Serina , Teratozoospermia , Humanos , Masculino , Animais , Camundongos , Teratozoospermia/genética , Teratozoospermia/metabolismo , Tubulina (Proteína)/metabolismo , Sêmen/metabolismo , Espermatozoides/metabolismo , Cabeça do Espermatozoide/metabolismo , Flagelos/metabolismo , Infertilidade Masculina/genética , Infertilidade Masculina/metabolismo , Mutação , Proteínas de Ligação ao GTP/metabolismo , D-Ala-D-Ala Carboxipeptidase Tipo Serina/genética , D-Ala-D-Ala Carboxipeptidase Tipo Serina/metabolismo
7.
Infect Immun ; 92(8): e0019324, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-38990045

RESUMO

Immunoglobulin A1 (IgA1) protease is a critical virulence factor of Haemophilus influenzae that facilitates bacterial mucosal infection. This study investigates the effect of iga gene polymorphism on the enzymatic activity of H. influenzae IgA1 protease. The IgA1 protease activity was examined in the H. influenzae Rd KW20 strain and 51 isolates. Genetic variations in iga and deduced amino acid substitutions affecting IgA1 protease activity were assessed. Machine learning tools and functional complementation assays were used to analyze the effects of identified substitutions on the stability and activity of IgA1 protease, respectively. All 51 isolates exhibited similar iga expression levels. No igaB expression was detected. According to comparisons with the reference Rd KW20 strain, four substitutions in the protease domain, 26 in the nonprotease passenger domain, and two in the ß-barrel domain were associated with the change in IgA1 protease activity. No substitutions in the catalytic site of IgA1 protease were observed. Logistic regression, receiver operating characteristic curves, Venn diagrams, and protein stability analyses revealed that the substitutions Asn352Lys, Pro353Ala, Lys356Asn, Gln916Lys, and Gly917Ser, which were located in the nonactive site of the passenger domain, were associated with decreases in IgA1 protease activity and stability, whereas Asn914Lys was associated with an increase in these events. Functional complementation assays revealed that the Asn914Lys substitution increased IgA1 protease activity in the Rd KW20 strain. This study identified substitutions in the nonactive site of the passenger domain that affect both the activity and stability of H. influenzae IgA1 protease.


Assuntos
Haemophilus influenzae , Haemophilus influenzae/genética , Haemophilus influenzae/enzimologia , Humanos , Substituição de Aminoácidos , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo , Serina Endopeptidases/química , Imunoglobulina A/metabolismo , Infecções por Haemophilus/microbiologia , Infecções por Haemophilus/imunologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/química
8.
Ann Surg ; 279(1): 138-146, 2024 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-37226826

RESUMO

OBJECTIVE: To compare the clinical and patient-reported outcomes of minimal access and conventional nipple-sparing mastectomy (C-NSM). The secondary outcomes investigated included medical costs and oncological safety. BACKGROUND: Minimal-access NSM has been increasingly applied in the treatment of patients with breast cancer. However, prospective multicenter trials comparing robotic-assisted NSM (R-NSM) versus C-NSM or endoscopic-assisted NSM (E-NSM) are lacking. METHODS: A prospectively designed 3-arm multicenter, nonrandomized trial (NCT04037852) was conducted from October 1, 2019 to December 31, 2021, to compare R-NSM with C-NSM or E-NSM. RESULTS: A total of 73 R-NSM, 74 C-NSM, and 84 E-NSM procedures were enrolled. The median wound length and operation time of C-NSM was (9 cm, 175 minutes), (4 cm, and 195 minutes) in R-NSM, and (4 cm and 222 minutes) in E-NSM. Complications were comparable among the groups. Better wound healing was observed in the minimal-access NSM group. The R-NSM procedure was 4000 and 2600 United States Dollars more expensive than C-NSM and E-NSM, respectively. Wound/scar and postoperative acute pain evaluation favored the use of minimal access NSM over C-NSM. Quality of life in terms of chronic breast/chest pain, mobility, and range of motion of the upper extremity showed no significant differences. The preliminary oncologic results showed no differences among the 3 groups. CONCLUSIONS: R-NSM or E-NSM is a safe alternative if compared with C-NSM in terms of perioperative morbidities, especially with better wound healing. The advantage of minimal access groups was higher wound-related satisfaction. Higher costs remain one of the major limiting factors in the widespread adoption of R-NSM.


Assuntos
Implantes de Mama , Neoplasias da Mama , Mamoplastia , Procedimentos Cirúrgicos Robóticos , Humanos , Feminino , Neoplasias da Mama/cirurgia , Neoplasias da Mama/etiologia , Mastectomia/métodos , Mamilos/cirurgia , Estudos Prospectivos , Qualidade de Vida , Mamoplastia/métodos , Medidas de Resultados Relatados pelo Paciente , Estudos Retrospectivos
9.
Mass Spectrom Rev ; 42(5): 1828-1847, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35603997

RESUMO

In the emergency department, it is important to rapidly identify the toxic substances that have led to acute poisoning because different toxicants or toxins cause poisoning through different mechanisms, requiring disparate therapeutic strategies and precautions against contraindicating actions, and diverse directions of clinical course monitoring and prediction of prognosis. Ambient ionization mass spectrometry, a state-of-the-art technology, has been proved to be a fast, accurate, and user-friendly tool for rapidly identifying toxicants like residual pesticides on fruits and vegetables. In view of this, developing an analytical platform that explores the application of such a cutting-edge technology in a novel direction has been initiated a research program, namely, the rapid identification of toxic substances which might have caused acute poisoning in patients who visit the emergency department and requires an accurate diagnosis for correct clinical decision-making to bring about corresponding data-guided management. This review includes (i) a narrative account of the breakthrough in emergency toxicology brought about by the advent of ambient ionization mass spectrometry and (ii) a thorough discussion about the clinical implications and technical limitations of such a promising innovation for promoting toxicological tests from tier two-level to tier one level.

10.
New Phytol ; 241(5): 2209-2226, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38084045

RESUMO

R-loops, three-stranded nucleic acid structures consisting of a DNA: RNA hybrid and displaced single-stranded DNA, play critical roles in gene expression and genome stability. How R-loop homeostasis is integrated into chloroplast gene expression remains largely unknown. We found an unexpected function of FtsHi1, an inner envelope membrane-bound AAA-ATPase in chloroplast R-loop homeostasis of Arabidopsis thaliana. Previously, this protein was shown to function as a component of the import motor complex for nuclear-encoded chloroplast proteins. However, this study provides evidence that FtsHi1 is an ATP-dependent helicase that efficiently unwinds both DNA-DNA and DNA-RNA duplexes, thereby preventing R-loop accumulation. Over-accumulation of R-loops could impair chloroplast transcription but not necessarily genome integrity. The dual function of FtsHi1 in both protein import and chloroplast gene expression may be important to coordinate the biogenesis of nuclear- and chloroplast-encoded subunits of multi-protein photosynthetic complexes. This study suggests a mechanical link between protein import and R-loop homeostasis in chloroplasts of higher plants.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Trifosfato de Adenosina/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Cloroplastos/metabolismo , DNA Helicases/genética , DNA Helicases/metabolismo , Transporte Proteico , Estruturas R-Loop , RNA/metabolismo , RNA Helicases/genética
11.
Arch Microbiol ; 206(7): 298, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38860999

RESUMO

A decreased chloramphenicol susceptibility in Haemophilus influenzae is commonly caused by the activity of chloramphenicol acetyltransferases (CATs). However, the involvement of membrane proteins in chloramphenicol susceptibility in H. influenzae remains unclear. In this study, chloramphenicol susceptibility testing, whole-genome sequencing, and analyses of membrane-related genes were performed in 51 H. influenzae isolates. Functional complementation assays and structure-based protein analyses were conducted to assess the effect of proteins with sequence substitutions on the minimum inhibitory concentration (MIC) of chloramphenicol in CAT-negative H. influenzae isolates. Six isolates were resistant to chloramphenicol and positive for type A-2 CATs. Of these isolates, A3256 had a similar level of CAT activity but a higher chloramphenicol MIC relative to the other resistant isolates; it also had 163 specific variations in 58 membrane genes. Regarding the CAT-negative isolates, logistic regression and receiver operator characteristic curve analyses revealed that 48T > G (Asn16Lys), 85 C > T (Leu29Phe), and 88 C > A (Leu30Ile) in HI_0898 (emrA), and 86T > G (Phe29Cys) and 141T > A (Ser47Arg) in HI_1177 (artM) were associated with enhanced chloramphenicol susceptibility, whereas 997G > A (Val333Ile) in HI_1612 (hmrM) was associated with reduced chloramphenicol susceptibility. Furthermore, the chloramphenicol MIC was lower in the CAT-negative isolates with EmrA-Leu29Phe/Leu30Ile or ArtM-Ser47Arg substitution and higher in those with HmrM-Val333Ile substitution, relative to their counterparts. The Val333Ile substitution was associated with enhanced HmrM protein stability and flexibility and increased chloramphenicol MICs in CAT-negative H. influenzae isolates. In conclusion, the substitution in H. influenzae multidrug efflux pump HmrM associated with reduced chloramphenicol susceptibility was characterised.


Assuntos
Substituição de Aminoácidos , Antibacterianos , Proteínas de Bactérias , Cloranfenicol , Haemophilus influenzae , Humanos , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Cloranfenicol/farmacologia , Cloranfenicol O-Acetiltransferase/genética , Cloranfenicol O-Acetiltransferase/metabolismo , Resistência ao Cloranfenicol/genética , Farmacorresistência Bacteriana Múltipla/genética , Infecções por Haemophilus/microbiologia , Haemophilus influenzae/efeitos dos fármacos , Haemophilus influenzae/genética , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Testes de Sensibilidade Microbiana , Sequenciamento Completo do Genoma
12.
BMC Med Imaging ; 24(1): 75, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38549082

RESUMO

BACKGROUND: Based on a longitudinal cohort design, the aim of this study was to investigate whether individual-based 18F fluorodeoxyglucose positron emission tomography (18F-FDG-PET) regional signals can predict dementia conversion in patients with mild cognitive impairment (MCI). METHODS: We included 44 MCI converters (MCI-C), 38 non-converters (MCI-NC), 42 patients with Alzheimer's disease with dementia, and 40 cognitively normal controls. Data from annual cognitive measurements, 3D T1 magnetic resonance imaging (MRI) scans, and 18F-FDG-PET scans were used for outcome analysis. An individual-based FDG-PET approach was applied using seven volumes of interest (VOIs), Z transformed using a normal FDG-PET template. Hypometabolism was defined as a Z score < -2 of regional standard uptake value ratio. For the longitudinal cognitive test scores, generalized estimating equations were used. A linear mixed-effects model was used to compare the temporal impact of cortical hypometabolism and cortical thickness degeneration. RESULTS: The clinical follow-up period was 6.6 ± 3.8 years (range 3.1 to 16.0 years). The trend of cognitive decline could differentiate MCI-C from MCI-NC after 3 years of follow-up. In the baseline 18F-FDG-PET scan of the patients with MCI, medial temporal lobe (MTL; 94.7% sensitivity, 80.5% specificity) and posterior cingulate cortex (PCC; 89.5% sensitivity, 73.1% specificity) hypometabolism predicted conversion with high accuracy. 18F-FDG-PET hypometabolism preceded dementia conversion at an interval of 3.70 ± 1.68 years and was earlier than volumetric changes, with the exception of the MTL. CONCLUSIONS: Our finding supports the use of individual-based 18F-FDG-PET analysis to predict MCI conversion to dementia. Reduced FDG-PET metabolism in the MTL and PCC were strongly associated with future cognitive decline in the MCI-C group. Changes in 18F-FDG-PET occurred 1 to 8 years prior to conversion to dementia. Progressive hypometabolism in the PCC, precuneus and lateral temporal lobe, but not MTL, preceded MRI findings at the MCI stage.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Humanos , Fluordesoxiglucose F18 , Progressão da Doença , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/metabolismo , Disfunção Cognitiva/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/métodos , Encéfalo/metabolismo
13.
Rheumatol Int ; 44(5): 805-817, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38470502

RESUMO

COVID-19 has been suggested as a possible trigger of disease flares in patients with rheumatoid arthritis (RA). However, factors associated with disease flares remain unknown. This study aimed to identify factors associated with breakthrough infection (BIs) and disease flares in patients with RA following COVID-19. We analysed data from RA patients who participated in the COVID-19 vaccination in autoimmune diseases (COVAD) study. Demographic data, patient-reported outcomes, comorbidities, pharmacologic treatment and details regarding disease flares were extracted from the COVAD database. Factors associated with disease flare-ups were determined by multivariate logistic regression analysis. The analysis comprised 1928 patients with RA who participated in the COVAD study. Younger age, Caucasian ethnicity, comorbidities with obstructive chronic pulmonary disease and asthma were associated with COVID-19 breakthrough infection. Moreover, younger age (odds ratio (OR): 0.98, 95% CI 0.96-0.99, p < 0.001), ethnicity other than Asian, past history of tuberculosis (OR: 3.80, 95% CI 1.12-12.94, p = 0.033), treatment with methotrexate (OR: 2.55, 95% CI: 1.56-4.17, p < 0.001), poor global physical health (OR: 1.07, 95% CI 1.00-1.15, p = 0.044) and mental health (OR: 0.91, 95% CI 0.87-0.95, p < 0.001) were independent factors associated disease flares in patients with RA. Our study highlights the impact of socio-demographic factors, clinical characteristics and mental health on disease flares in patients with RA. These insights may help determine relevant strategies to proactively manage RA patients at risk of flares.


Assuntos
Artrite Reumatoide , Infecções Irruptivas , COVID-19 , Humanos , Exacerbação dos Sintomas , Vacinas contra COVID-19/uso terapêutico , SARS-CoV-2 , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/epidemiologia
14.
J Neuroophthalmol ; 44(1): 107-111, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36626595

RESUMO

BACKGROUND: Internuclear ophthalmoplegia (INO) is a result of insult to the medial longitudinal fasciculus (MLF). Clinicoradiological correlation in patients with INO has been reported to be poor; however, prior studies have used low resolution MRI imaging techniques and included patients with subclinical INO. We aimed to determine the sensitivity of modern MRI interpreted by a specialist neuroradiologist to detect clinically evident INO. METHODS: A retrospective chart review of patients in 2 tertiary University-affiliated neuro-ophthalmology practices with the diagnosis of INO. MRI scans of all patients were reviewed and interpreted by a fellowship-trained neuroradiologist for the presence of lesion in MLF and concordance with the original imaging report. RESULTS: Forty-five patients were included in the study: 33 with demyelinating disease, 11 with stroke, and 1 with intracranial mass. A visible MLF lesion was present in 25/33 demyelinating cases and 7/11 ischemic cases. Lesions in 2 cases in each group were identified only after review by a fellowship-trained neuroradiologist. In demyelinating INO, patients with a visible MLF lesion were more likely to show other brainstem (72%) and supratentorial (51%) white matter lesions. CONCLUSIONS: In 25% of patients with demyelinating INO and 33% of patients with ischemic INO, no visible lesion was identified on current high-quality MRI imaging. Review of imaging by a neuroradiologist increased the possibility of lesion been identified.


Assuntos
Esclerose Múltipla , Transtornos da Motilidade Ocular , Oftalmoplegia , Humanos , Transtornos da Motilidade Ocular/diagnóstico por imagem , Transtornos da Motilidade Ocular/etiologia , Estudos Retrospectivos , Imageamento por Ressonância Magnética/métodos , Tronco Encefálico , Oftalmoplegia/diagnóstico
15.
Psychiatry Clin Neurosci ; 78(8): 446-455, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38864501

RESUMO

BACKGROUND: Tau-first cognitive proteinopathy (TCP) denotes a clinical phenotype of Alzheimer disease (AD) showing Florzolotau(18F) positron emission tomography (PET) positivity but a negative amyloid status. AIM: We explored the biological property of tau using longitudinal cognitive and neuroimaging data in TCP and compared with late-onset AD (LOAD). METHOD: We enrolled 56 patients with LOAD, 34 patients with TCP, and 26 cognitive unimpaired controls. All of the participants had historical data of 2 to 4 three-dimensional T1 images and 2 to 6 annual cognitive evaluations over a follow-up period of 7 years. Tau topography was measured using Florzolotau(18F) PET. In the LOAD and TCP groups, we constructed tau or gray matter clusters covarying with the cognitive measurements. We used mediator analysis to explore the regional tau load as predictor, gray matter partitions as mediators, and significant cognitive test scores as outcomes. Longitudinal cognitive decline and cortical thickness degeneration pattern were analyzed using a linear mixed-effects model. RESULTS: The TCP group had longitudinal declines in nonexecutive domains. The deterministic factor predicting the short-term memory score in TCP was the hippocampal volume and not directly via the medial and lateral temporal tau load. These features formed the conceptual differences with LOAD. DISCUSSION: The biological properties of tau and the longitudinal cognitive-imaging trajectory support the conceptual distinction between TCP and LOAD. TCP represents one specific entity featuring salient short-term memory impairment, declines in nonexecutive domains, a slower gray matter degenerative pattern, and a restricted impact of tau.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Substância Cinzenta , Tomografia por Emissão de Pósitrons , Proteínas tau , Humanos , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/patologia , Masculino , Feminino , Idoso , Proteínas tau/metabolismo , Estudos Longitudinais , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Substância Cinzenta/metabolismo , Disfunção Cognitiva/diagnóstico por imagem , Pessoa de Meia-Idade , Tauopatias/diagnóstico por imagem , Tauopatias/patologia , Imageamento por Ressonância Magnética , Neuroimagem , Idoso de 80 Anos ou mais , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/patologia , Córtex Cerebral/metabolismo , Carbolinas
16.
Int J Mol Sci ; 25(11)2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38891795

RESUMO

The purpose of this study was to investigate whether plasma biomarkers can help to diagnose, differentiate from Alzheimer disease (AD), and stage cognitive performance in patients with positron emission tomography (PET)-confirmed primary age-related tauopathy, termed tau-first cognitive proteinopathy (TCP) in this study. In this multi-center study, we enrolled 285 subjects with young-onset AD (YOAD; n = 55), late-onset AD (LOAD; n = 96), TCP (n = 44), and cognitively unimpaired controls (CTL; n = 90) and analyzed plasma Aß42/Aß40, pTau181, neurofilament light (NFL), and total-tau using single-molecule assays. Amyloid and tau centiloids reflected pathological burden, and hippocampal volume reflected structural integrity. Receiver operating characteristic curves and areas under the curves (AUCs) were used to determine the diagnostic accuracy of plasma biomarkers compared to hippocampal volume and amyloid and tau centiloids. The Mini-Mental State Examination score (MMSE) served as the major cognitive outcome. Logistic stepwise regression was used to assess the overall diagnostic accuracy, combining fluid and structural biomarkers and a stepwise linear regression model for the significant variables for MMSE. For TCP, tau centiloid reached the highest AUC for diagnosis (0.79), while pTau181 could differentiate TCP from YOAD (accuracy 0.775) and LOAD (accuracy 0.806). NFL reflected the clinical dementia rating in TCP, while pTau181 (rho = 0.3487, p = 0.03) and Aß42/Aß40 (rho = -0.36, p = 0.02) were significantly correlated with tau centiloid. Hippocampal volume (unstandardized ß = 4.99, p = 0.01) outperformed all of the fluid biomarkers in predicting MMSE scores in the TCP group. Our results support the superiority of tau PET to diagnose TCP, pTau181 to differentiate TCP from YOAD or LOAD, and NFL for functional staging.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Biomarcadores , Tomografia por Emissão de Pósitrons , Proteínas tau , Humanos , Doença de Alzheimer/sangue , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/diagnóstico , Proteínas tau/sangue , Biomarcadores/sangue , Masculino , Feminino , Tomografia por Emissão de Pósitrons/métodos , Idoso , Peptídeos beta-Amiloides/sangue , Pessoa de Meia-Idade , Cognição , Hipocampo/diagnóstico por imagem , Hipocampo/patologia , Hipocampo/metabolismo , Proteínas de Neurofilamentos/sangue , Idoso de 80 Anos ou mais , Amnésia/sangue , Amnésia/diagnóstico por imagem , Amnésia/diagnóstico , Curva ROC , Relevância Clínica
17.
Int J Mol Sci ; 25(11)2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38891875

RESUMO

Transcranial focused ultrasound stimulation (tFUS) has emerged as a promising neuromodulation technique that delivers acoustic energy with high spatial resolution for inducing long-term potentiation (LTP)- or depression (LTD)-like plasticity. The variability in the primary effects of tFUS-induced plasticity could be due to different stimulation patterns, such as intermittent versus continuous, and is an aspect that requires further detailed exploration. In this study, we developed a platform to evaluate the neuromodulatory effects of intermittent and continuous tFUS on motor cortical plasticity before and after tFUS application. Three groups of rats were exposed to either intermittent, continuous, or sham tFUS. We analyzed the neuromodulatory effects on motor cortical excitability by examining changes in motor-evoked potentials (MEPs) elicited by transcranial magnetic stimulation (TMS). We also investigated the effects of different stimulation patterns on excitatory and inhibitory neural biomarkers, examining c-Fos and glutamic acid decarboxylase (GAD-65) expression using immunohistochemistry staining. Additionally, we evaluated the safety of tFUS by analyzing glial fibrillary acidic protein (GFAP) expression. The current results indicated that intermittent tFUS produced a facilitation effect on motor excitability, while continuous tFUS significantly inhibited motor excitability. Furthermore, neither tFUS approach caused injury to the stimulation sites in rats. Immunohistochemistry staining revealed increased c-Fos and decreased GAD-65 expression following intermittent tFUS. Conversely, continuous tFUS downregulated c-Fos and upregulated GAD-65 expression. In conclusion, our findings demonstrate that both intermittent and continuous tFUS effectively modulate cortical excitability. The neuromodulatory effects may result from the activation or deactivation of cortical neurons following tFUS intervention. These effects are considered safe and well-tolerated, highlighting the potential for using different patterns of tFUS in future clinical neuromodulatory applications.


Assuntos
Potencial Evocado Motor , Córtex Motor , Plasticidade Neuronal , Estimulação Magnética Transcraniana , Animais , Córtex Motor/fisiologia , Ratos , Masculino , Potencial Evocado Motor/fisiologia , Estimulação Magnética Transcraniana/métodos , Proteínas Proto-Oncogênicas c-fos/metabolismo , Ondas Ultrassônicas , Ratos Sprague-Dawley , Proteína Glial Fibrilar Ácida/metabolismo , Glutamato Descarboxilase/metabolismo
18.
J Sci Food Agric ; 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39319876

RESUMO

BACKGROUND: Global food loss and waste have raised environmental concerns regarding the generation of greenhouse gases (e.g., carbon dioxide and methane gas), which directly contribute to climate change. To address these concerns, the present research aims to upcycle food waste into an alternative culture medium for the cultivation of microalgae. Various parameters including pretreatment of food waste (i.e., autoclave and non-autoclave), concentration of food waste culture medium (i.e., 10%, 30%, 50%, 70%, 90% and 100%), harvesting efficiency and biochemical compounds of Chlorella sp. microalgae were carried out. RESULTS: Based on the preliminary findings, the highest biomass concentration obtained from 10% food waste culture medium in the autoclave for Chlorella sp., including strains FSP-E, ESP-31 and CY-1, were 2.869 ± 0.022, 2.385 ± 0.018 and 0.985 ± 0.0026 g L-1, respectively. Since Chlorella vulgaris FSP-E exhibited the highest biomass concentration, this microalgal strain was selected to examine the subsequent parameters. Cultivation of C. vulgaris FSP-E in 100FW achieves a biomass concentration of 4.465 ± 0.008 g L-1 with biochemical compounds of 6.94 ± 1.396, 248.24 ± 0.976 and 406.23 ± 0.593 mg g-1 for lipids, carbohydrates and proteins, respectively. CONCLUSION: This study shows that using food waste as an alternative culture medium for C. vulgaris FSP-E can achieve substantial biomass productivity and biochemical content. This research work would contribute to the concept of net zero emission and transitioning toward a circular bioeconomy by upcycling food waste as an alternative culture medium for the cultivation of microalgae. © 2024 Society of Chemical Industry.

19.
Int Wound J ; 21(2): e14710, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38838072

RESUMO

To explore the knowledge, attitudes and practice (KAP) status of preventing pressure injury among clinical nurses working in paediatric ICU, and to examine factors affecting nurses' KAP. A questionnaire survey was conducted among 1906 paediatric ICU nurses in 18 children's hospitals by convenience sampling method. The survey tools were self-designed general data questionnaire, KAP questionnaire for the prevention of pressure injury and the influencing factors were analysed. A total of 1906 valid questionnaires were collected. The scores of overall KPA, knowledge, attitudes, and practice were 101.24 ± 17.22, 20.62 ± 9.63, 54.93 ± 5.81and 25.67 ± 6.76, respectively. The results of multiple linear regression analysis showed that education background, professional title, age and specialist nurse were the main influencing factor of nurses' knowledge of preventing PI; education background and specialist nurse were the main influencing factors of nurses' attitudes of preventing PI; knowledge, attitudes and education background were the main influencing factors of nurses' practice of preventing PI. Paediatric ICU nurses have a positive attitude towards the prevention of PI, but their knowledge and practice need to be improved. According to different characteristics of nurses, nursing managers should carry out training on the knowledge of prevention of PI to establish a positive attitude, so as to drive the change of nursing practice and improve the nursing practice level of ICU nurses to prevent of PI.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Unidades de Terapia Intensiva Pediátrica , Úlcera por Pressão , Humanos , Úlcera por Pressão/prevenção & controle , Feminino , Masculino , Inquéritos e Questionários , Adulto , Atitude do Pessoal de Saúde , Recursos Humanos de Enfermagem Hospitalar/psicologia , Enfermagem de Cuidados Críticos/métodos , Pessoa de Meia-Idade , Adulto Jovem , Competência Clínica/estatística & dados numéricos
20.
Plant Cell Physiol ; 2023 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-37498958

RESUMO

The formation of chloroplasts can be traced back to an ancient event in which a eukaryotic host cell containing mitochondria ingested a cyanobacterium. Since then, chloroplasts have retained many characteristics of their bacterial ancestor, including their transcription and translation machinery. In this review, recent research on the maturation of rRNA and ribosome assembly in chloroplasts is explored, along with their crucial role in plant survival and their implications for plant acclimation to changing environments. A comparison is made between the ribosome composition and auxiliary factors of ancient and modern chloroplasts, providing insights into the evolution of ribosome assembly factors. Although the chloroplast contains ancient proteins with conserved functions in ribosome assembly, newly evolved factors have also emerged to help plants acclimate to changes in their environment and internal signals. Overall, this review offers a comprehensive analysis of the molecular mechanisms underlying chloroplast ribosome assembly and highlights the importance of this process in plant survival, acclimation, and adaptation.

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