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1.
Cell ; 184(25): 6193-6206.e14, 2021 12 09.
Artículo en Inglés | MEDLINE | ID: mdl-34838160

RESUMEN

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.


Asunto(s)
Técnicas Biosensibles/métodos , Células/ultraestructura , Microscopía Fluorescente/métodos , Análisis de la Célula Individual/métodos , Línea Celular Tumoral , Humanos
2.
Cell ; 180(6): 1144-1159.e20, 2020 03 19.
Artículo en Inglés | MEDLINE | ID: mdl-32169217

RESUMEN

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.


Asunto(s)
Arabidopsis/metabolismo , Transporte de Proteínas/fisiología , Sistema de Translocación de Arginina Gemela/metabolismo , Proteínas de Cloroplastos/metabolismo , Cloroplastos/metabolismo , Membranas Intracelulares/metabolismo , Proteínas de la Membrana/metabolismo , Biogénesis de Organelos , Orgánulos/metabolismo , Transición de Fase , Proteínas de Plantas/metabolismo , Tilacoides/metabolismo , Sistema de Translocación de Arginina Gemela/fisiología
3.
Mol Cell ; 70(4): 602-613.e3, 2018 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-29775578

RESUMEN

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.


Asunto(s)
Procesamiento Proteico-Postraduccional , Receptores de Citocinas/metabolismo , Selenoproteínas/metabolismo , Proteasas Ubiquitina-Específicas/metabolismo , Ubiquitina/metabolismo , Células HEK293 , Células HeLa , Células Hep G2 , Humanos , Dominios Proteicos , Proteolisis , Receptores de Citocinas/genética , Proteasas Ubiquitina-Específicas/genética
4.
Genes Dev ; 32(17-18): 1161-1174, 2018 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-30115631

RESUMEN

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.


Asunto(s)
Empalme Alternativo , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Cadherinas/metabolismo , Células Madre Embrionarias/metabolismo , Ribonucleoproteína Heterogénea-Nuclear Grupo F-H/metabolismo , Antígenos CD , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Cadherinas/genética , Diferenciación Celular/genética , Línea Celular , Células Madre Embrionarias/citología , Exones , Regulación de la Expresión Génica , Humanos , Precursores del ARN/química , ARN Mensajero/química , Secuencias Reguladoras de Ácido Ribonucleico
5.
EMBO J ; 40(7): e105846, 2021 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-33469951

RESUMEN

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.


Asunto(s)
Proteolisis , Ubiquitinación , Secuencias de Aminoácidos , Línea Celular Tumoral , Células HEK293 , Humanos , Transporte de Proteínas , Proteoma/química , Proteoma/metabolismo , Receptores de Citocinas/metabolismo
6.
J Cell Mol Med ; 28(2): e18031, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37937809

RESUMEN

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.


Asunto(s)
Infertilidad Masculina , D-Ala-D-Ala Carboxipeptidasa de Tipo Serina , Teratozoospermia , Humanos , Masculino , Animales , Ratones , Teratozoospermia/genética , Teratozoospermia/metabolismo , Tubulina (Proteína)/metabolismo , Semen/metabolismo , Espermatozoides/metabolismo , Cabeza del Espermatozoide/metabolismo , Flagelos/metabolismo , Infertilidad Masculina/genética , Infertilidad Masculina/metabolismo , Mutación , Proteínas de Unión al GTP/metabolismo , D-Ala-D-Ala Carboxipeptidasa de Tipo Serina/genética , D-Ala-D-Ala Carboxipeptidasa de Tipo Serina/metabolismo
7.
Infect Immun ; 92(8): e0019324, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-38990045

RESUMEN

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.


Asunto(s)
Haemophilus influenzae , Haemophilus influenzae/genética , Haemophilus influenzae/enzimología , Humanos , Sustitución de Aminoácidos , Serina Endopeptidasas/genética , Serina Endopeptidasas/metabolismo , Serina Endopeptidasas/química , Inmunoglobulina A/metabolismo , Infecciones por Haemophilus/microbiología , Infecciones por Haemophilus/inmunología , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/química
8.
Ann Surg ; 279(1): 138-146, 2024 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-37226826

RESUMEN

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.


Asunto(s)
Implantes de Mama , Neoplasias de la Mama , Mamoplastia , Procedimientos Quirúrgicos Robotizados , Humanos , Femenino , Neoplasias de la Mama/cirugía , Neoplasias de la Mama/etiología , Mastectomía/métodos , Pezones/cirugía , Estudios Prospectivos , Calidad de Vida , Mamoplastia/métodos , Medición de Resultados Informados por el Paciente , Estudios Retrospectivos
9.
Mass Spectrom Rev ; 42(5): 1828-1847, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35603997

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-38084045

RESUMEN

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.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Adenosina Trifosfato/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Cloroplastos/metabolismo , ADN Helicasas/genética , ADN Helicasas/metabolismo , Transporte de Proteínas , Estructuras R-Loop , ARN/metabolismo , ARN Helicasas/genética
11.
Respir Res ; 25(1): 377, 2024 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-39420386

RESUMEN

BACKGROUND: Dual bronchodilator therapy, consisting of a long-acting beta-agonist (LABA) and a long-acting muscarinic antagonist (LAMA), has proven effective for patients with chronic obstructive pulmonary disease (COPD). However, it remains uncertain whether there are efficacy differences between current and former smokers with COPD. This study aims to explore the effectiveness of LABA/LAMA therapies in both these groups. METHODS: The TOReTO trial assessed lung function, symptoms, health status, the occurrence of exacerbations, clinically significant exacerbations, and the use of LABA/LAMA therapies. These therapies include Tio/Olo, umeclidinium/vilanterol (Umec/Vi), and umeclidinium/vilanterol (Umec/Vi) are used in patients with COPD. The study examined the differences in outcomes between current and former smokers. To balance the baseline characteristics, propensity score matching (PSM) was employed. RESULTS: Data from 967 patients were collected. After PSM, the time to the first acute exacerbation in current smokers was analyzed separately for the three treatment groups and was significantly different between them (p = 0.0457). Among, there are differences in the occurrence of acute exacerbation between treatment and smoking status in Umec/Vi (p = 0.0114). There is no significant difference in the treatment of former smokers among the three different groups of LABA/LAMA fixed-dose combinations (p = 0.3079). COPD-related symptoms remained stable throughout the treatment period. There were no significant differences in symptom scores, including CAT and mMRC, among the three groups at the end of the study. CONCLUSIONS: The three fixed-dose combinations of LABA/LAMA showed no difference in reducing exacerbations in former smokers but did show differences in current smokers. This trend has clinical significance, and future research will be conducted to control influencing variables to validate this point. However, due to the non-randomized study design, these findings should be interpreted with caution.


Asunto(s)
Broncodilatadores , Antagonistas Muscarínicos , Enfermedad Pulmonar Obstructiva Crónica , Fumadores , Humanos , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Masculino , Femenino , Broncodilatadores/administración & dosificación , Broncodilatadores/uso terapéutico , Anciano , Persona de Mediana Edad , Antagonistas Muscarínicos/administración & dosificación , Antagonistas Muscarínicos/uso terapéutico , Progresión de la Enfermedad , Resultado del Tratamiento , Fumar/epidemiología , Fumar/efectos adversos , Agonistas de Receptores Adrenérgicos beta 2/administración & dosificación , Agonistas de Receptores Adrenérgicos beta 2/uso terapéutico , Combinación de Medicamentos , Quimioterapia Combinada , Quinuclidinas
12.
J Biomed Sci ; 31(1): 94, 2024 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-39379923

RESUMEN

Recent breakthroughs in cancer immunotherapies have emphasized the importance of harnessing the immune system for treating cancer. Vaccines, which have traditionally been used to promote protective immunity against pathogens, are now being explored as a method to target cancer neoantigens. Over the past few years, extensive preclinical research and more than a hundred clinical trials have been dedicated to investigating various approaches to neoantigen discovery and vaccine formulations, encouraging development of personalized medicine. Nucleic acids (DNA and mRNA) have become particularly promising platform for the development of these cancer immunotherapies. This shift towards nucleic acid-based personalized vaccines has been facilitated by advancements in molecular techniques for identifying neoantigens, antigen prediction methodologies, and the development of new vaccine platforms. Generating these personalized vaccines involves a comprehensive pipeline that includes sequencing of patient tumor samples, data analysis for antigen prediction, and tailored vaccine manufacturing. In this review, we will discuss the various shared and personalized antigens used for cancer vaccine development and introduce strategies for identifying neoantigens through the characterization of gene mutation, transcription, translation and post translational modifications associated with oncogenesis. In addition, we will focus on the most up-to-date nucleic acid vaccine platforms, discuss the limitations of cancer vaccines as well as provide potential solutions, and raise key clinical and technical considerations in vaccine development.


Asunto(s)
Antígenos de Neoplasias , Vacunas contra el Cáncer , Neoplasias , Medicina de Precisión , Humanos , Vacunas contra el Cáncer/inmunología , Vacunas contra el Cáncer/uso terapéutico , Medicina de Precisión/métodos , Antígenos de Neoplasias/inmunología , Neoplasias/inmunología , Neoplasias/terapia , Desarrollo de Vacunas/métodos , Ácidos Nucleicos/inmunología , Inmunoterapia/métodos
13.
Arch Microbiol ; 206(7): 298, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38860999

RESUMEN

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.


Asunto(s)
Sustitución de Aminoácidos , Antibacterianos , Proteínas Bacterianas , Cloranfenicol , Haemophilus influenzae , Humanos , Antibacterianos/farmacología , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Cloranfenicol/farmacología , Cloranfenicol O-Acetiltransferasa/genética , Cloranfenicol O-Acetiltransferasa/metabolismo , Resistencia al Cloranfenicol/genética , Farmacorresistencia Bacteriana Múltiple/genética , Infecciones por Haemophilus/microbiología , Haemophilus influenzae/efectos de los fármacos , Haemophilus influenzae/genética , Proteínas de Transporte de Membrana/genética , Proteínas de Transporte de Membrana/metabolismo , Pruebas de Sensibilidad Microbiana , Secuenciación Completa del Genoma
14.
BMC Med Imaging ; 24(1): 75, 2024 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-38549082

RESUMEN

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.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Humanos , Fluorodesoxiglucosa F18 , Progresión de la Enfermedad , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/metabolismo , Disfunción Cognitiva/diagnóstico por imagen , Tomografía de Emisión de Positrones/métodos , Encéfalo/metabolismo
15.
Rheumatol Int ; 44(5): 805-817, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38470502

RESUMEN

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.


Asunto(s)
Artritis Reumatoide , Infección Irruptiva , COVID-19 , Humanos , Brote de los Síntomas , Vacunas contra la COVID-19/uso terapéutico , SARS-CoV-2 , Artritis Reumatoide/tratamiento farmacológico , Artritis Reumatoide/epidemiología
16.
J Neuroophthalmol ; 44(1): 107-111, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36626595

RESUMEN

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.


Asunto(s)
Esclerosis Múltiple , Trastornos de la Motilidad Ocular , Oftalmoplejía , Humanos , Trastornos de la Motilidad Ocular/diagnóstico por imagen , Trastornos de la Motilidad Ocular/etiología , Estudios Retrospectivos , Imagen por Resonancia Magnética/métodos , Tronco Encefálico , Oftalmoplejía/diagnóstico
17.
Psychiatry Clin Neurosci ; 78(8): 446-455, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38864501

RESUMEN

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.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Sustancia Gris , Tomografía de Emisión de Positrones , Proteínas tau , Humanos , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/patología , Masculino , Femenino , Anciano , Proteínas tau/metabolismo , Estudios Longitudinales , Sustancia Gris/diagnóstico por imagen , Sustancia Gris/patología , Sustancia Gris/metabolismo , Disfunción Cognitiva/diagnóstico por imagen , Persona de Mediana Edad , Tauopatías/diagnóstico por imagen , Tauopatías/patología , Imagen por Resonancia Magnética , Neuroimagen , Anciano de 80 o más Años , Corteza Cerebral/diagnóstico por imagen , Corteza Cerebral/patología , Corteza Cerebral/metabolismo , Carbolinas
18.
Med Teach ; : 1-7, 2024 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-39382279

RESUMEN

PURPOSE: Incorporating social determinants of health (SDH) into medical education is crucial. However, there are limited data on standard education models and comprehensive SDH curricula in Taiwan are insufficient. This study presents a systematic SDH curriculum instructed primarily by social workers for postgraduate doctors and aims to examine the training outcomes of the innovative curriculum. METHOD: This study assessed training outcomes using Kirkpatrick model levels 1 and 2 regarding trainees' satisfaction and improvement of their knowledge and skills in written and standardized patient (SP) pre- and posttests conducted between 1 August 2021 and 31 July 2022. RESULTS: A total of 28 trainees completed the training. The trainees' overall satisfaction score regarding the curriculum was high (4.6 out of 5). The median pretest scores for the written and SP tests were 66.25 ± 14.38 and 14.50 ± 5.13, respectively, whereas the median posttest scores were 80.00 ± 7.50 and 20.50 ± 6.13, respectively. Both written and SP posttest scores were significantly improved compared to the pretest scores (p < .001). CONCLUSIONS: The presented education model significantly improved postgraduate doctors' SDH knowledge and biopsychosocial assessment skills, and received high satisfaction scores from the trainees. Adopting social workers as primary teachers may enhance interdisciplinary collaboration between social workers and trainee doctors.

19.
Int J Mol Sci ; 25(11)2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38891795

RESUMEN

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.


Asunto(s)
Enfermedad de Alzheimer , Péptidos beta-Amiloides , Biomarcadores , Tomografía de Emisión de Positrones , Proteínas tau , Humanos , Enfermedad de Alzheimer/sangre , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/diagnóstico , Proteínas tau/sangre , Biomarcadores/sangre , Masculino , Femenino , Tomografía de Emisión de Positrones/métodos , Anciano , Péptidos beta-Amiloides/sangre , Persona de Mediana Edad , Cognición , Hipocampo/diagnóstico por imagen , Hipocampo/patología , Hipocampo/metabolismo , Proteínas de Neurofilamentos/sangre , Anciano de 80 o más Años , Amnesia/sangre , Amnesia/diagnóstico por imagen , Amnesia/diagnóstico , Curva ROC , Relevancia Clínica
20.
Int J Mol Sci ; 25(11)2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38891875

RESUMEN

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.


Asunto(s)
Potenciales Evocados Motores , Corteza Motora , Plasticidad Neuronal , Estimulación Magnética Transcraneal , Animales , Corteza Motora/fisiología , Ratas , Masculino , Potenciales Evocados Motores/fisiología , Estimulación Magnética Transcraneal/métodos , Proteínas Proto-Oncogénicas c-fos/metabolismo , Ondas Ultrasónicas , Ratas Sprague-Dawley , Proteína Ácida Fibrilar de la Glía/metabolismo , Glutamato Descarboxilasa/metabolismo
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