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1.
Cell ; 187(3): 596-608.e17, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38194966

RESUMEN

BA.2.86, a recently identified descendant of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron BA.2 sublineage, contains ∼35 mutations in the spike (S) protein and spreads in multiple countries. Here, we investigated whether the virus exhibits altered biological traits, focusing on S protein-driven viral entry. Employing pseudotyped particles, we show that BA.2.86, unlike other Omicron sublineages, enters Calu-3 lung cells with high efficiency and in a serine- but not cysteine-protease-dependent manner. Robust lung cell infection was confirmed with authentic BA.2.86, but the virus exhibited low specific infectivity. Further, BA.2.86 was highly resistant against all therapeutic antibodies tested, efficiently evading neutralization by antibodies induced by non-adapted vaccines. In contrast, BA.2.86 and the currently circulating EG.5.1 sublineage were appreciably neutralized by antibodies induced by the XBB.1.5-adapted vaccine. Collectively, BA.2.86 has regained a trait characteristic of early SARS-CoV-2 lineages, robust lung cell entry, and evades neutralizing antibodies. However, BA.2.86 exhibits low specific infectivity, which might limit transmissibility.


Asunto(s)
Anticuerpos Neutralizantes , Anticuerpos Antivirales , COVID-19 , SARS-CoV-2 , Humanos , Anticuerpos Neutralizantes/metabolismo , Anticuerpos Antivirales/metabolismo , Caspasas/metabolismo , COVID-19/inmunología , COVID-19/virología , Pulmón/virología , SARS-CoV-2/clasificación , SARS-CoV-2/genética , SARS-CoV-2/patogenicidad , SARS-CoV-2/fisiología , Internalización del Virus , Glicoproteína de la Espiga del Coronavirus/genética
2.
Cell ; 186(21): 4676-4693.e29, 2023 10 12.
Artículo en Inglés | MEDLINE | ID: mdl-37729907

RESUMEN

The assembly of the neuronal and other major cell type programs occurred early in animal evolution. We can reconstruct this process by studying non-bilaterians like placozoans. These small disc-shaped animals not only have nine morphologically described cell types and no neurons but also show coordinated behaviors triggered by peptide-secreting cells. We investigated possible neuronal affinities of these peptidergic cells using phylogenetics, chromatin profiling, and comparative single-cell genomics in four placozoans. We found conserved cell type expression programs across placozoans, including populations of transdifferentiating and cycling cells, suggestive of active cell type homeostasis. We also uncovered fourteen peptidergic cell types expressing neuronal-associated components like the pre-synaptic scaffold that derive from progenitor cells with neurogenesis signatures. In contrast, earlier-branching animals like sponges and ctenophores lacked this conserved expression. Our findings indicate that key neuronal developmental and effector gene modules evolved before the advent of cnidarian/bilaterian neurons in the context of paracrine cell signaling.


Asunto(s)
Evolución Biológica , Invertebrados , Neuronas , Animales , Ctenóforos/genética , Expresión Génica , Neuronas/fisiología , Filogenia , Análisis de la Célula Individual , Invertebrados/citología , Invertebrados/genética , Invertebrados/metabolismo , Comunicación Paracrina
3.
Cell ; 185(7): 1223-1239.e20, 2022 03 31.
Artículo en Inglés | MEDLINE | ID: mdl-35290801

RESUMEN

While CRISPR screens are helping uncover genes regulating many cell-intrinsic processes, existing approaches are suboptimal for identifying extracellular gene functions, particularly in the tissue context. Here, we developed an approach for spatial functional genomics called Perturb-map. We applied Perturb-map to knock out dozens of genes in parallel in a mouse model of lung cancer and simultaneously assessed how each knockout influenced tumor growth, histopathology, and immune composition. Moreover, we paired Perturb-map and spatial transcriptomics for unbiased analysis of CRISPR-edited tumors. We found that in Tgfbr2 knockout tumors, the tumor microenvironment (TME) was converted to a fibro-mucinous state, and T cells excluded, concomitant with upregulated TGFß and TGFß-mediated fibroblast activation, indicating that TGFß-receptor loss on cancer cells increased TGFß bioavailability and its immunosuppressive effects on the TME. These studies establish Perturb-map for functional genomics within the tissue at single-cell resolution with spatial architecture preserved and provide insight into how TGFß responsiveness of cancer cells can affect the TME.


Asunto(s)
Neoplasias , Microambiente Tumoral , Animales , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas/genética , Genómica , Ratones , Neoplasias/genética , Factor de Crecimiento Transformador beta/genética
4.
Immunity ; 55(9): 1627-1644.e7, 2022 09 13.
Artículo en Inglés | MEDLINE | ID: mdl-35977543

RESUMEN

The apolipoprotein E4 (APOE4) allele is associated with an increased risk of Alzheimer disease and a decreased risk of glaucoma, but the underlying mechanisms remain poorly understood. Here, we found that in two mouse glaucoma models, microglia transitioned to a neurodegenerative phenotype characterized by upregulation of Apoe and Lgals3 (Galectin-3), which were also upregulated in human glaucomatous retinas. Mice with targeted deletion of Apoe in microglia or carrying the human APOE4 allele were protected from retinal ganglion cell (RGC) loss, despite elevated intraocular pressure (IOP). Similarly to Apoe-/- retinal microglia, APOE4-expressing microglia did not upregulate neurodegeneration-associated genes, including Lgals3, following IOP elevation. Genetic and pharmacologic targeting of Galectin-3 ameliorated RGC degeneration, and Galectin-3 expression was attenuated in human APOE4 glaucoma samples. These results demonstrate that impaired activation of APOE4 microglia is protective in glaucoma and that the APOE-Galectin-3 signaling can be targeted to treat this blinding disease.


Asunto(s)
Apolipoproteína E4 , Glaucoma , Animales , Apolipoproteína E4/genética , Apolipoproteína E4/metabolismo , Apolipoproteína E4/uso terapéutico , Apolipoproteínas E/genética , Apolipoproteínas E/metabolismo , Modelos Animales de Enfermedad , Galectina 3/genética , Galectina 3/metabolismo , Galectina 3/uso terapéutico , Glaucoma/tratamiento farmacológico , Glaucoma/genética , Glaucoma/metabolismo , Humanos , Ratones , Microglía/metabolismo
5.
Nat Immunol ; 19(9): 942-953, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30111894

RESUMEN

The sensing of microbial genetic material by leukocytes often elicits beneficial pro-inflammatory cytokines, but dysregulated responses can cause severe pathogenesis. Genome-wide association studies have linked the gene encoding phospholipase D3 (PLD3) to Alzheimer's disease and have linked PLD4 to rheumatoid arthritis and systemic sclerosis. PLD3 and PLD4 are endolysosomal proteins whose functions are obscure. Here, PLD4-deficient mice were found to have an inflammatory disease, marked by elevated levels of interferon-γ (IFN-γ) and splenomegaly. These phenotypes were traced to altered responsiveness of PLD4-deficient dendritic cells to ligands of the single-stranded DNA sensor TLR9. Macrophages from PLD3-deficient mice also had exaggerated TLR9 responses. Although PLD4 and PLD3 were presumed to be phospholipases, we found that they are 5' exonucleases, probably identical to spleen phosphodiesterase, that break down TLR9 ligands. Mice deficient in both PLD3 and PLD4 developed lethal liver inflammation in early life, which indicates that both enzymes are needed to regulate inflammatory cytokine responses via the degradation of nucleic acids.


Asunto(s)
Células Dendríticas/fisiología , Endosomas/metabolismo , Exonucleasas/metabolismo , Hepatitis/genética , Macrófagos/fisiología , Glicoproteínas de Membrana/metabolismo , Fosfolipasa D/metabolismo , Enfermedad de Alzheimer/genética , Animales , Artritis Reumatoide/genética , ADN de Cadena Simple/inmunología , Exonucleasas/genética , Estudio de Asociación del Genoma Completo , Humanos , Interferón gamma/metabolismo , Glicoproteínas de Membrana/genética , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Fosfolipasa D/genética , Esclerodermia Sistémica/genética , Transducción de Señal , Receptor Toll-Like 9/metabolismo
6.
Immunity ; 54(12): 2908-2921.e6, 2021 12 14.
Artículo en Inglés | MEDLINE | ID: mdl-34788600

RESUMEN

Viral mutations are an emerging concern in reducing SARS-CoV-2 vaccination efficacy. Second-generation vaccines will need to elicit neutralizing antibodies against sites that are evolutionarily conserved across the sarbecovirus subgenus. Here, we immunized mice containing a human antibody repertoire with diverse sarbecovirus receptor-binding domains (RBDs) to identify antibodies targeting conserved sites of vulnerability. Antibodies with broad reactivity against diverse clade B RBDs targeting the conserved class 4 epitope, with recurring IGHV/IGKV pairs, were readily elicited but were non-neutralizing. However, rare class 4 antibodies binding this conserved RBD supersite showed potent neutralization of SARS-CoV-2 and all variants of concern. Structural analysis revealed that the neutralizing ability of cross-reactive antibodies was reserved only for those with an elongated CDRH3 that extends the antiparallel beta-sheet RBD core and orients the antibody light chain to obstruct ACE2-RBD interactions. These results identify a structurally defined pathway for vaccine strategies eliciting escape-resistant SARS-CoV-2 neutralizing antibodies.


Asunto(s)
Betacoronavirus/fisiología , Vacunas contra la COVID-19/inmunología , Infecciones por Coronavirus/inmunología , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/fisiología , Glicoproteína de la Espiga del Coronavirus/metabolismo , Animales , Anticuerpos Neutralizantes/metabolismo , Anticuerpos Antivirales/metabolismo , Secuencia Conservada/genética , Evolución Molecular , Humanos , Inmunización , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Unión Proteica , Dominios Proteicos/genética , Glicoproteína de la Espiga del Coronavirus/genética , Glicoproteína de la Espiga del Coronavirus/inmunología , Desarrollo de Vacunas
7.
J Proteome Res ; 23(5): 1615-1633, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38649144

RESUMEN

Autophagy supervises the proteostasis and survival of B lymphocytic cells. Trk-fused gene (TFG) promotes autophagosome-lysosome flux in murine CH12 B cells, as well as their survival. Hence, quantitative proteomics of CH12tfgKO and WT B cells in combination with lysosomal inhibition should identify proteins that are prone to lysosomal degradation and contribute to autophagy and B cell survival. Lysosome inhibition via NH4Cl unexpectedly reduced a number of proteins but increased a large cluster of translational, ribosomal, and mitochondrial proteins, independent of TFG. Hence, we propose a role for lysosomes in ribophagy in B cells. TFG-regulated proteins include CD74, BCL10, or the immunoglobulin JCHAIN. Gene ontology (GO) analysis reveals that proteins regulated by TFG alone, or in concert with lysosomes, localize to mitochondria and membrane-bound organelles. Likewise, TFG regulates the abundance of metabolic enzymes, such as ALDOC and the fatty acid-activating enzyme ACOT9. To test consequently for a function of TFG in lipid metabolism, we performed shotgun lipidomics of glycerophospholipids. Total phosphatidylglycerol is more abundant in CH12tfgKO B cells. Several glycerophospholipid species with similar acyl side chains, such as 36:2 phosphatidylethanolamine and 36:2 phosphatidylinositol, show a dysequilibrium. We suggest a role for TFG in lipid homeostasis, mitochondrial functions, translation, and metabolism in B cells.


Asunto(s)
Autofagia , Linfocitos B , Glicerofosfolípidos , Lisosomas , Animales , Ratones , Linfocitos B/metabolismo , Glicerofosfolípidos/metabolismo , Metabolismo de los Lípidos , Lipidómica/métodos , Lisosomas/metabolismo , Mitocondrias/metabolismo , Proteómica/métodos
8.
J Am Chem Soc ; 146(27): 18298-18305, 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38916582

RESUMEN

The superconducting critical temperature of H3S ranks among the highest measured, at 203 K. This impressive value stems from a singularity in the electronic density-of-states, induced by a flat-band region that consists of saddle points. The peak sits right at the Fermi level, so that it gives rise to a giant electron-phonon coupling constant. In this work, we show how atomic orbital interactions and space group symmetry work in concert to shape the singularity. The body-centered cubic Brillouin Zone offers a unique 2D hypersurface in reciprocal space: fully connecting squares with two different high-symmetry points at the corners, Γ and H, and a third one in the center, N. Orbital mixing leads to the collapse of fully connected 1D saddle point lines around the square centers, due to a symmetry-enforced s-p energy inversion between Γ and H. The saddle-point states are invariably nonbonding, which explains the unconventionally weak response of the superconductor's critical temperature to pressure. Although H3S appears to be a unique case, the theory shows how it is possible to engineer flat bands and singularities in 3D lattices through symmetry considerations.

9.
Neurobiol Dis ; 199: 106588, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38960101

RESUMEN

Clinical and preclinical evidence has demonstrated an increased risk for neuropsychiatric disorders following prenatal cannabinoid exposure. However, given the phytochemical complexity of cannabis, there is a need to understand how specific components of cannabis may contribute to these neurodevelopmental risks later in life. To investigate this, a rat model of prenatal cannabinoid exposure was utilized to examine the impacts of specific cannabis constituents (Δ9-tetrahydrocannabinol [THC]; cannabidiol [CBD]) alone and in combination on future neuropsychiatric liability in male and female offspring. Prenatal THC and CBD exposure were associated with low birth weight. At adolescence, offspring displayed sex-specific behavioural changes in anxiety, temporal order and social cognition, and sensorimotor gating. These phenotypes were associated with sex and treatment-specific neuronal and gene transcriptional alterations in the prefrontal cortex, and ventral hippocampus, regions where the endocannabinoid system is implicated in affective and cognitive development. Electrophysiology and RT-qPCR analysis in these regions implicated dysregulation of the endocannabinoid system and balance of excitatory and inhibitory signalling in the developmental consequences of prenatal cannabinoids. These findings reveal critical insights into how specific cannabinoids can differentially impact the developing fetal brains of males and females to enhance subsequent neuropsychiatric risk.


Asunto(s)
Conducta Animal , Cannabidiol , Dronabinol , Hipocampo , Corteza Prefrontal , Efectos Tardíos de la Exposición Prenatal , Modelos Animales , Animales , Ratas , Dronabinol/toxicidad , Cannabidiol/toxicidad , Factores Sexuales , Corteza Prefrontal/efectos de los fármacos , Hipocampo/efectos de los fármacos , Masculino , Femenino , Embarazo , Conducta Animal/efectos de los fármacos , Ratas Wistar , Memoria/efectos de los fármacos , Ansiedad/inducido químicamente , Cognición/efectos de los fármacos , Conducta Impulsiva/efectos de los fármacos , Psicotrópicos/toxicidad
10.
Eur Radiol ; 34(1): 308-317, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37552256

RESUMEN

OBJECTIVES: Gender differences have been reported to influence medical training. We investigated gender differences encountered during training in interventional radiology maneuvers. METHODS: Catheter handling was analyzed under standardized conditions in 64 participants naïve to endovascular procedures (26 women, 38 men). Objective (e.g., catheter pathway, catheter movements, required time) and subjective parameters (stress level) were recorded. The NASA-Task Load Index (NASA-TLX; 1-20 points) was used to assess participants' stress levels and perceived workload. RESULTS: In the easier tasks, no significant differences between male and female participants regarding catheter handling were observed. In the most complex task, female participants took themselves more time (688 ± 363 vs. 501 ± 230 s; p = 0.02), asked for help more frequently (n = 19 vs. n = 8) and earlier than men (203 ± 94 vs. 305 ± 142 s; p = 0.049), whereas men stood out by more agitated catheter handling (6.0 ± 1.8 vs. 4.8 ± 1.6 movements/s; p = 0.005). Overall, female participants perceived tasks to be more difficult (11.5 ± 4.2 vs. 9.6 ± 3.3; p = 0.016), perceived higher stress levels (8.9 ± 4.9 vs. 6.3 ± 4.4; p = 0.037), and rated their own performance lower (9.12 ± 3.3 vs. 11.3 ± 3.3; p = 0.009). However, female participants were able to correlate self-assessed with objective parameters correctly (r between -0.555 and -0.469; p = 0.004-0.018), whereas male participants failed to correctly rate their performance (p between 0.34 and 0.73). Stress levels correlated with objective parameters in males (r between 0.4 and 0.587; p < 0.005), but not in female participants. CONCLUSION: Perceived stress levels, self-evaluation skills, and catheter handling differ greatly between untrained male and female participants trying to solve interventional radiological tasks. These gender-specific differences should be considered in interventional radiology training. CLINICAL RELEVANCE STATEMENT: As psychological aspects may influence individual working strategies gender-specific differences in self-perception while learning interventional radiology maneuvers could be essential regarding success in teaching and treatment outcomes. KEY POINTS: • After performing standardized training, 38 male and 26 female volunteers showed significant differences regarding objective and self-assessed performance, as well as in perceived workload while performing simulated endovascular catheter maneuvers. • After solving simulated endovascular radiological tasks, female participants were able to self-assess their objective performance much more accurately than male participants. • Women took more time to solve simulated endovascular tasks and asked earlier and more frequently for help than men.


Asunto(s)
Procedimientos Endovasculares , Radiología Intervencionista , Humanos , Masculino , Femenino , Factores Sexuales , Carga de Trabajo/psicología , Aprendizaje
11.
J Chem Phys ; 161(4)2024 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-39037145

RESUMEN

In this work, we study the effect of nanoconfinement on the hydration properties of model hydrophobic pores and carbon nanotubes, determining their wetting propensity and the conditions for geometrically induced dehydration. By employing a recently introduced water structural index, we aim at two main goals: (1) to accurately quantify the local hydrophobicity and predict the drying transitions in such systems, and (2) to provide a molecular rationalization of the wetting process. In this sense, we will further discuss the number and strength of the interactions required by the water molecules to promote wetting. In the case of graphene-like surfaces, an explanation for their unexpectedly significant hydrophilicity will also be provided. On the one hand, the structural index will show that the net attraction to the dense carbon network that a water molecule experiences through several simultaneous weak interactions is sufficient to give rise to hydrophilic behavior. On the other hand, we will show that an additional effect is also at play: the hydrating water molecule is retained on the surface by a smooth exchange of such simultaneous weak interactions, as if "sliding" on graphene.

12.
J Obstet Gynaecol Can ; 46(8): 102618, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39089469

RESUMEN

OBJECTIVE: To summarize the current evidence and to make recommendations for the diagnosis and management of intrahepatic cholestasis of pregnancy. TARGET POPULATION: Pregnant people with intrahepatic cholestasis of pregnancy. OPTIONS: Diagnosing the condition using fasting or non-fasting bile acids, classifying disease severity, determining what treatment to offer, establishing how to monitor for antenatal fetal wellbeing, identifying when to perform elective birth. BENEFITS, HARMS, AND COSTS: Individuals with intrahepatic cholestasis of pregnancy are at increased risk of adverse perinatal outcomes including preterm birth, neonatal respiratory distress and admission to a neonatal intensive care unit, with an increased risk of stillbirth when bile acid levels are ≥100 µmol/L. There is inequity in bile acid testing availability and timely access to results, along with uncertainly of how to treat, monitor. and ultimately deliver these pregnancies. Optimization of diagnostic and management protocols can improve maternal and fetal postnatal outcomes. EVIDENCE: Medline, PubMed, Embase, and the Cochrane Library were searched from inception to March 2023, using medical subject headings (MeSH) and keywords related to pregnancy, intrahepatic cholestasis of pregnancy, bile acids, pruritis, ursodeoxycholic acid, and stillbirth. This document presents an abstraction of the evidence rather than a methodological review. VALIDATION METHODS: The authors rated the quality of evidence and strength of recommendations using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. See Appendix A (Tables A1 for definitions and A2 for interpretations). INTENDED AUDIENCE: Obstetric care providers, including obstetricians, family physicians, nurses, midwives, maternal-fetal medicine specialists, and radiologists. SOCIAL MEDIA ABSTRACT: Intrahepatic cholestasis of pregnancy requires adequate diagnosis with non-fasting bile acid levels which guide optimal management and delivery timing. SUMMARY STATEMENTS: RECOMMENDATIONS.


Asunto(s)
Colestasis Intrahepática , Complicaciones del Embarazo , Humanos , Colestasis Intrahepática/diagnóstico , Colestasis Intrahepática/terapia , Femenino , Embarazo , Complicaciones del Embarazo/diagnóstico , Complicaciones del Embarazo/terapia , Canadá , Ácidos y Sales Biliares/sangre , Obstetricia/normas
13.
J Strength Cond Res ; 38(6): 1033-1040, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38349394

RESUMEN

ABSTRACT: Ketelhut, S, Ketelhut, K, Ketelhut, SR, and Ketelhut, RG. Effects of school-based high-intensity interval training on hemodynamic parameters and heart rate variability: A randomized controlled trial. J Strength Cond Res 38(6): 1033-1040, 2024-The purpose of this study was to assess the effects of a child-specific school-based high-intensity interval training (HIIT) implemented into physical education (PE) classes on various hemodynamic parameters and heart rate variability indices. Forty-six students (age 11 ± 1 year) were randomized into an intervention (INT n = 22) and a control group (CON n = 24). During a 12-week period, the INT and CON groups participated in regular PE twice weekly (45-90 minutes). The INT group received HIIT during the first 20 minutes of the 2 PE classes. Systolic and diastolic blood pressure, total peripheral resistance, aortic pulse wave velocity (aPWV), heart rate, SD of normal to normal heartbeat intervals, the root mean square of successive differences between normal heartbeats (RMSSD), the proportion of differences between adjacent normal to normal heartbeat intervals of more than 50 ms, low-frequency power, high-frequency power, and the LF/HF ratio were assessed before and after the experimental period. A p value ≤0.05 was considered statistically significant. Forty students (20 INT; 20 CON) were included in the analysis. A significant time × group interaction was detected for aPWV ( p = 0.05, η2 = 0.099), RMSSD ( p = 0.010, η2 = 0.161), low-frequency power ( p = 0.009, η2 = 0.165), high-frequency power ( p < 0.001, η2 = 0.272), and the LF/HF ratio ( p < 0.001, η2 = 0.354). The INT group revealed significant improvements for the respective parameters. School-based HIIT can induce improvements in cardiovascular parameters. These results highlight the potential of embedding HIIT within the school setting, offering a time-efficient exercise intervention.


Asunto(s)
Frecuencia Cardíaca , Entrenamiento de Intervalos de Alta Intensidad , Educación y Entrenamiento Físico , Humanos , Entrenamiento de Intervalos de Alta Intensidad/métodos , Frecuencia Cardíaca/fisiología , Masculino , Niño , Femenino , Educación y Entrenamiento Físico/métodos , Presión Sanguínea/fisiología , Hemodinámica/fisiología , Análisis de la Onda del Pulso , Instituciones Académicas , Resistencia Vascular/fisiología
14.
Eur J Immunol ; 52(6): 970-977, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35253229

RESUMEN

Effective vaccines and monoclonal antibodies have been developed against coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, the appearance of virus variants with higher transmissibility and pathogenicity is a major concern because of their potential to escape vaccines and clinically approved SARS-CoV-2- antibodies. Here, we use flow cytometry-based binding and pseudotyped SARS-CoV-2 neutralization assays to determine the efficacy of boost immunization and therapeutic antibodies to neutralize the dominant Omicron variant. We provide compelling evidence that the third vaccination with BNT162b2 increases the amount of neutralizing serum antibodies against Delta and Omicron variants, albeit to a lower degree when compared to the parental Wuhan strain. Therefore, a third vaccination is warranted to increase titers of protective serum antibodies, especially in the case of the Omicron variant. We also found that most clinically approved and otherwise potent therapeutic antibodies against the Delta variant failed to recognize and neutralize the Omicron variant. In contrast, some antibodies under preclinical development potentially neutralized the Omicron variant. Our studies also support using a flow cytometry-based antibody binding assay to rapidly monitor therapeutic candidates and serum titers against emerging SARS-CoV-2 variants.


Asunto(s)
Antineoplásicos Inmunológicos , COVID-19 , Anticuerpos Monoclonales , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Vacuna BNT162 , Vacunas contra la COVID-19 , Humanos , SARS-CoV-2 , Vacunación
15.
Eur J Immunol ; 52(5): 770-783, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-34355795

RESUMEN

TRIANNI mice carry an entire set of human immunoglobulin V region gene segments and are a powerful tool to rapidly isolate human monoclonal antibodies. After immunizing these mice with DNA encoding the spike protein of SARS-CoV-2 and boosting with spike protein, we identified 29 hybridoma antibodies that reacted with the SARS-CoV-2 spike protein. Nine antibodies neutralize SARS-CoV-2 infection at IC50 values in the subnanomolar range. ELISA-binding studies and DNA sequence analyses revealed one cluster of three clonally related neutralizing antibodies that target the receptor-binding domain and compete with the cellular receptor hACE2. A second cluster of six clonally related neutralizing antibodies bind to the N-terminal domain of the spike protein without competing with the binding of hACE2 or cluster 1 antibodies. SARS-CoV-2 mutants selected for resistance to an antibody from one cluster are still neutralized by an antibody from the other cluster. Antibodies from both clusters markedly reduced viral spread in mice transgenic for human ACE2 and protected the animals from SARS-CoV-2-induced weight loss. The two clusters of potent noncompeting SARS-CoV-2 neutralizing antibodies provide potential candidates for therapy and prophylaxis of COVID-19. The study further supports transgenic animals with a human immunoglobulin gene repertoire as a powerful platform in pandemic preparedness initiatives.


Asunto(s)
COVID-19 , Glicoproteína de la Espiga del Coronavirus , Animales , Anticuerpos Monoclonales , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Humanos , Ratones , SARS-CoV-2
16.
Mov Disord ; 38(5): 717-731, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36959763

RESUMEN

Tremor is the most frequent human movement disorder, and its diagnosis is based on clinical assessment. Yet finding the accurate clinical diagnosis is not always straightforward. Fine-tuning of clinical diagnostic criteria over the past few decades, as well as device-based qualitative analysis, has resulted in incremental improvements to diagnostic accuracy. Accelerometric assessments are commonplace, enabling clinicians to capture high-resolution oscillatory properties of tremor, which recently have been the focus of various machine-learning (ML) studies. In this context, the application of ML models to accelerometric recordings provides the potential for less-biased classification and quantification of tremor disorders. However, if implemented incorrectly, ML can result in spurious or nongeneralizable results and misguided conclusions. This work summarizes and highlights recent developments in ML tools for tremor research, with a focus on supervised ML. We aim to highlight the opportunities and limitations of such approaches and provide future directions while simultaneously guiding the reader through the process of applying ML to analyze tremor data. We identify the need for the movement disorder community to take a more proactive role in the application of these novel analytical technologies, which so far have been predominantly pursued by the engineering and data analysis field. Ultimately, big-data approaches offer the possibility to identify generalizable patterns but warrant meaningful translation into clinical practice. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Asunto(s)
Trastornos del Movimiento , Temblor , Humanos , Temblor/diagnóstico , Trastornos del Movimiento/diagnóstico , Aprendizaje Automático
17.
Mov Disord ; 38(6): 1077-1082, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36750755

RESUMEN

BACKGROUND: Skin biopsy is a potential tool for the premortem confirmation of an α-synucleinopathy. OBJECTIVE: The aim was to assess the aggregation assay real-time quaking-induced conversion (RT-QuIC) of skin biopsy lysates to confirm isolated rapid eye movement sleep behavior disorder (iRBD) as an α-synucleinopathy. METHODS: Skin biopsies of patients with iRBD, Parkinson's disease (PD), and controls were analyzed using RT-QuIC and immunohistochemical detection of phospho-α-synuclein. RESULTS: α-Synuclein aggregation was detected in 97.4% of iRBD patients (78.4% of iRBD biopsies), 87.2% of PD patients (70% of PD biopsies), and 13% of controls (7.9% of control biopsies), with a higher seeding activity in iRBD compared to PD. RT-QuIC was more sensitive but less specific than immunohistochemistry. CONCLUSIONS: Dermal RT-QuIC is a sensitive method to detect α-synuclein aggregation in iRBD, and high seeding activity may indicate a strong involvement of dermal nerve fibers in these patients. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Asunto(s)
Enfermedad de Parkinson , Trastorno de la Conducta del Sueño REM , Sinucleinopatías , Humanos , alfa-Sinucleína , Sinucleinopatías/diagnóstico , Trastorno de la Conducta del Sueño REM/diagnóstico , Trastorno de la Conducta del Sueño REM/patología , Enfermedad de Parkinson/diagnóstico , Enfermedad de Parkinson/patología , Biopsia
18.
Prenat Diagn ; 43(8): 1044-1055, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36738445

RESUMEN

OBJECTIVE: To evaluate the role of mid-trimester placental growth factor (PlGF) in patients with abnormal circulating levels of first-trimester biomarkers. METHODS: Retrospective cohort study including singleton pregnancies complicated by abnormal first-trimester biomarkers (2017-2020). Pregnancies complicated with chromosomal/structural anomalies were excluded. All patients had ultrasound imaging including uterine artery Doppler combined with measurement of maternal circulating PlGF. Sonographic findings, maternal and perinatal outcomes, and placental histopathology were compared between pregnancies with normal and low (<10th percentile for gestational age) PlGF levels. The diagnostic accuracy of PlGF for the prediction of specific placental-mediated complications was compared with the uterine artery Doppler assessment and additional sonographic findings. RESULTS: Seventy-one pregnancies were assessed, of which 35 (49.3%) had low PlGF levels. Maternal sociodemographic characteristics, nulliparity, and aspirin consumption were comparable. In comparison with patients with normal PlGF levels, individuals with low PlGF levels had a higher rate of fetal growth restriction (EFW <3rd centile; 42.9% vs. 8.3%, p = 0.001), preterm-preeclampsia (22.9% vs. 0%, p = 0.002), preterm delivery <34 weeks (54.3% vs. 8.3%, p < 0.001) and maternal vascular malperfusion placental pathology (72.7% vs. 21.7%, p < 0.001) following delivery. Adjusting for uterine artery Doppler and fetal biometry status, mid-trimester low PlGF remained significantly associated with these placental-mediated complications. The predictive capacity of PlGF outperformed ultrasound imaging with only minimal diagnostic improvement when ultrasound information was combined with PlGF status. CONCLUSION: In pregnancies with unexplained abnormal first-trimester biomarkers, mid-trimester PlGF outperformed a comprehensive ultrasound assessment in the identification of a subset of patients destined to develop placental dysfunction. This blood test may be an alternative initial approach in this context, especially where access to specialist care is more geographically challenging.


Asunto(s)
Placenta , Preeclampsia , Recién Nacido , Embarazo , Humanos , Femenino , Factor de Crecimiento Placentario , Primer Trimestre del Embarazo , Estudios Retrospectivos , Ultrasonografía Doppler , Biomarcadores , Arteria Uterina/diagnóstico por imagen
19.
BMC Pregnancy Childbirth ; 23(1): 553, 2023 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-37532986

RESUMEN

BACKGROUND: Pregnant people are particularly vulnerable to SARS-CoV-2 infection and to ensuing severe illness. Predicting adverse maternal and perinatal outcomes could aid clinicians in deciding on hospital admission and early initiation of treatment in affected individuals, streamlining the triaging processes. METHODS: An international repository of 1501 SARS-CoV-2-positive cases in pregnancy was created, consisting of demographic variables, patient comorbidities, laboratory markers, respiratory parameters, and COVID-19-related symptoms. Data were filtered, preprocessed, and feature selection methods were used to obtain the optimal feature subset for training a variety of machine learning models to predict maternal or fetal/neonatal death or critical illness. RESULTS: The Random Forest model demonstrated the best performance among the trained models, correctly identifying 83.3% of the high-risk patients and 92.5% of the low-risk patients, with an overall accuracy of 89.0%, an AUC of 0.90 (95% Confidence Interval 0.83 to 0.95), and a recall, precision, and F1 score of 0.85, 0.94, and 0.89, respectively. This was achieved using a feature subset of 25 features containing patient characteristics, symptoms, clinical signs, and laboratory markers. These included maternal BMI, gravidity, parity, existence of pre-existing conditions, nicotine exposure, anti-hypertensive medication administration, fetal malformations, antenatal corticosteroid administration, presence of dyspnea, sore throat, fever, fatigue, duration of symptom phase, existence of COVID-19-related pneumonia, need for maternal oxygen administration, disease-related inpatient treatment, and lab markers including sFLT-1/PlGF ratio, platelet count, and LDH. CONCLUSIONS: We present the first COVID-19 prognostication pipeline specifically for pregnant patients while utilizing a large SARS-CoV-2 in pregnancy data repository. Our model accurately identifies those at risk of severe illness or clinical deterioration, presenting a promising tool for advancing personalized medicine in pregnant patients with COVID-19.


Asunto(s)
COVID-19 , Complicaciones Infecciosas del Embarazo , Femenino , Humanos , Recién Nacido , Embarazo , COVID-19/diagnóstico , Muerte Fetal , Parto , Complicaciones Infecciosas del Embarazo/diagnóstico , Complicaciones Infecciosas del Embarazo/terapia , Estudios Retrospectivos , SARS-CoV-2 , Resultado del Embarazo
20.
Respiration ; 102(2): 120-133, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36566741

RESUMEN

BACKGROUND: Lung function impairment persists in some patients for months after acute coronavirus disease 2019 (COVID-19). Long-term lung function, radiological features, and their association remain to be clarified. OBJECTIVES: We aimed to prospectively investigate lung function and radiological abnormalities over 12 months after severe and non-severe COVID-19. METHODS: 584 patients were included in the Swiss COVID-19 lung study. We assessed lung function at 3, 6, and 12 months after acute COVID-19 and compared chest computed tomography (CT) imaging to lung functional abnormalities. RESULTS: At 12 months, diffusion capacity for carbon monoxide (DLCOcorr) was lower after severe COVID-19 compared to non-severe COVID-19 (74.9% vs. 85.2% predicted, p < 0.001). Similarly, minimal oxygen saturation on 6-min walk test and total lung capacity were lower after severe COVID-19 (89.6% vs. 92.2%, p = 0.004, respectively, 88.2% vs. 95.1% predicted, p = 0.011). The difference for forced vital capacity (91.6% vs. 96.3% predicted, p = 0.082) was not statistically significant. Between 3 and 12 months, lung function improved in both groups and differences in DLCO between non-severe and severe COVID-19 patients decreased. In patients with chest CT scans at 12 months, we observed a correlation between radiological abnormalities and reduced lung function. While the overall extent of radiological abnormalities diminished over time, the frequency of mosaic attenuation and curvilinear patterns increased. CONCLUSIONS: In this prospective cohort study, patients who had severe COVID-19 had diminished lung function over the first year compared to those after non-severe COVID-19, albeit with a greater extent of recovery in the severe disease group.


Asunto(s)
COVID-19 , Insuficiencia Respiratoria , Humanos , Estudios Prospectivos , Suiza/epidemiología , Pulmón/diagnóstico por imagen
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