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1.
Cell ; 184(5): 1330-1347.e13, 2021 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-33636130

RESUMO

Osteoclasts are large multinucleated bone-resorbing cells formed by the fusion of monocyte/macrophage-derived precursors that are thought to undergo apoptosis once resorption is complete. Here, by intravital imaging, we reveal that RANKL-stimulated osteoclasts have an alternative cell fate in which they fission into daughter cells called osteomorphs. Inhibiting RANKL blocked this cellular recycling and resulted in osteomorph accumulation. Single-cell RNA sequencing showed that osteomorphs are transcriptionally distinct from osteoclasts and macrophages and express a number of non-canonical osteoclast genes that are associated with structural and functional bone phenotypes when deleted in mice. Furthermore, genetic variation in human orthologs of osteomorph genes causes monogenic skeletal disorders and associates with bone mineral density, a polygenetic skeletal trait. Thus, osteoclasts recycle via osteomorphs, a cell type involved in the regulation of bone resorption that may be targeted for the treatment of skeletal diseases.


Assuntos
Reabsorção Óssea/patologia , Osteoclastos/patologia , Ligante RANK/metabolismo , Animais , Apoptose , Reabsorção Óssea/metabolismo , Fusão Celular , Células Cultivadas , Humanos , Macrófagos/citologia , Camundongos , Osteocondrodisplasias/tratamento farmacológico , Osteocondrodisplasias/genética , Osteocondrodisplasias/metabolismo , Osteocondrodisplasias/patologia , Osteoclastos/metabolismo , Transdução de Sinais
3.
Annu Rev Neurosci ; 45: 295-316, 2022 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-35316612

RESUMO

Vocal communication is a critical feature of social interaction across species; however, the relation between such behavior in humans and nonhumans remains unclear. To enable comparative investigation of this topic, we review the literature pertinent to interactive language use and identify the superset of cognitive operations involved in generating communicative action. We posit these functions comprise three intersecting multistep pathways: (a) the Content Pathway, which selects the movements constituting a response; (b) the Timing Pathway, which temporally structures responses; and (c) the Affect Pathway, which modulates response parameters according to internal state. These processing streams form the basis of the Convergent Pathways for Interaction framework, which provides a conceptual model for investigating the cognitive and neural computations underlying vocal communication across species.


Assuntos
Idioma , Vocalização Animal , Animais , Humanos , Vocalização Animal/fisiologia
4.
N Engl J Med ; 390(16): 1493-1504, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38657245

RESUMO

BACKGROUND: Most moderate-to-late-preterm infants need nutritional support until they are feeding exclusively on their mother's breast milk. Evidence to guide nutrition strategies for these infants is lacking. METHODS: We conducted a multicenter, factorial, randomized trial involving infants born at 32 weeks 0 days' to 35 weeks 6 days' gestation who had intravenous access and whose mothers intended to breast-feed. Each infant was assigned to three interventions or their comparators: intravenous amino acid solution (parenteral nutrition) or dextrose solution until full feeding with milk was established; milk supplement given when maternal milk was insufficient or mother's breast milk exclusively with no supplementation; and taste and smell exposure before gastric-tube feeding or no taste and smell exposure. The primary outcome for the parenteral nutrition and the milk supplement interventions was the body-fat percentage at 4 months of corrected gestational age, and the primary outcome for the taste and smell intervention was the time to full enteral feeding (150 ml per kilogram of body weight per day or exclusive breast-feeding). RESULTS: A total of 532 infants (291 boys [55%]) were included in the trial. The mean (±SD) body-fat percentage at 4 months was similar among the infants who received parenteral nutrition and those who received dextrose solution (26.0±5.4% vs. 26.2±5.2%; adjusted mean difference, -0.20; 95% confidence interval [CI], -1.32 to 0.92; P = 0.72) and among the infants who received milk supplement and those who received mother's breast milk exclusively (26.3±5.3% vs. 25.8±5.4%; adjusted mean difference, 0.65; 95% CI, -0.45 to 1.74; P = 0.25). The time to full enteral feeding was similar among the infants who were exposed to taste and smell and those who were not (5.8±1.5 vs. 5.7±1.9 days; P = 0.59). Secondary outcomes were similar across interventions. Serious adverse events occurred in one infant. CONCLUSIONS: This trial of routine nutrition interventions to support moderate-to-late-preterm infants until full nutrition with mother's breast milk was possible did not show any effects on the time to full enteral feeding or on body composition at 4 months of corrected gestational age. (Funded by the Health Research Council of New Zealand and others; DIAMOND Australian New Zealand Clinical Trials Registry number, ACTRN12616001199404.).


Assuntos
Aleitamento Materno , Nutrição Enteral , Recém-Nascido Prematuro , Nutrição Parenteral , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Aminoácidos/administração & dosagem , Idade Gestacional , Glucose/administração & dosagem , Leite Humano , Olfato , Paladar , Apoio Nutricional , Soluções de Nutrição Parenteral/uso terapêutico , Adiposidade
5.
N Engl J Med ; 390(8): 723-735, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38381675

RESUMO

BACKGROUND: Polycythemia vera is a chronic myeloproliferative neoplasm characterized by erythrocytosis. Rusfertide, an injectable peptide mimetic of the master iron regulatory hormone hepcidin, restricts the availability of iron for erythropoiesis. The safety and efficacy of rusfertide in patients with phlebotomy-dependent polycythemia vera are unknown. METHODS: In part 1 of the international, phase 2 REVIVE trial, we enrolled patients in a 28-week dose-finding assessment of rusfertide. Part 2 was a double-blind, randomized withdrawal period in which we assigned patients, in a 1:1 ratio, to receive rusfertide or placebo for 12 weeks. The primary efficacy end point was a response, defined by hematocrit control, absence of phlebotomy, and completion of the trial regimen during part 2. Patient-reported outcomes were assessed by means of the modified Myeloproliferative Neoplasm Symptom Assessment Form (MPN-SAF) patient diary (scores range from 0 to 10, with higher scores indicating greater severity of symptoms). RESULTS: Seventy patients were enrolled in part 1 of the trial, and 59 were assigned to receive rusfertide (30 patients) or placebo (29 patients) in part 2. The estimated mean (±SD) number of phlebotomies per year was 8.7±2.9 during the 28 weeks before the first dose of rusfertide and 0.6±1.0 during part 1 (estimated difference, 8.1 phlebotomies per year). The mean maximum hematocrit was 44.5±2.2% during part 1 as compared with 50.0±5.8% during the 28 weeks before the first dose of rusfertide. During part 2, a response was observed in 60% of the patients who received rusfertide as compared with 17% of those who received placebo (P = 0.002). Between baseline and the end of part 1, rusfertide treatment was associated with a decrease in individual symptom scores on the MPN-SAF in patients with moderate or severe symptoms at baseline. During parts 1 and 2, grade 3 adverse events occurred in 13% of the patients, and none of the patients had a grade 4 or 5 event. Injection-site reactions of grade 1 or 2 in severity were common. CONCLUSIONS: In patients with polycythemia vera, rusfertide treatment was associated with a mean hematocrit of less than 45% during the 28-week dose-finding period, and the percentage of patients with a response during the 12-week randomized withdrawal period was greater with rusfertide than with placebo. (Funded by Protagonist Therapeutics; REVIVE ClinicalTrials.gov number, NCT04057040.).


Assuntos
Hepcidinas , Peptídeos , Policitemia Vera , Humanos , Hematócrito , Hepcidinas/administração & dosagem , Hepcidinas/uso terapêutico , Ferro , Policitemia/diagnóstico , Policitemia/tratamento farmacológico , Policitemia/etiologia , Policitemia Vera/tratamento farmacológico , Policitemia Vera/complicações , Policitemia Vera/diagnóstico , Peptídeos/administração & dosagem , Peptídeos/uso terapêutico , Injeções , Método Duplo-Cego , Fármacos Hematológicos/administração & dosagem , Fármacos Hematológicos/uso terapêutico
6.
Cell ; 144(4): 566-76, 2011 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-21335238

RESUMO

TAp63α, a homolog of the p53 tumor suppressor, is a quality control factor in the female germline. Remarkably, already undamaged oocytes express high levels of the protein, suggesting that TAp63α's activity is under tight control of an inhibitory mechanism. Biochemical studies have proposed that inhibition requires the C-terminal transactivation inhibitory domain. However, the structural mechanism of TAp63α inhibition remains unknown. Here, we show that TAp63α is kept in an inactive dimeric state. We reveal that relief of inhibition leads to tetramer formation with ∼20-fold higher DNA affinity. In vivo, phosphorylation-triggered tetramerization of TAp63α is not reversible by dephosphorylation. Furthermore, we show that a helix in the oligomerization domain of p63 is crucial for tetramer stabilization and competes with the transactivation domain for the same binding site. Our results demonstrate how TAp63α is inhibited by complex domain-domain interactions that provide the basis for regulating quality control in oocytes.


Assuntos
Oócitos/metabolismo , Fosfoproteínas/química , Fosfoproteínas/metabolismo , Transativadores/química , Transativadores/metabolismo , Animais , DNA/metabolismo , Dimerização , Feminino , Raios gama , Camundongos , Modelos Moleculares , Fosforilação , Multimerização Proteica , Proteína Supressora de Tumor p53/metabolismo
7.
Nature ; 583(7816): 375-378, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32632215

RESUMO

The coexistence of superconducting and correlated insulating states in magic-angle twisted bilayer graphene1-11 prompts fascinating questions about their relationship. Independent control of the microscopic mechanisms that govern these phases could help uncover their individual roles and shed light on their intricate interplay. Here we report on direct tuning of electronic interactions in this system by changing the separation distance between the graphene and a metallic screening layer12,13. We observe quenching of correlated insulators in devices with screening layer separations that are smaller than the typical Wannier orbital size of 15 nanometres and with twist angles that deviate slightly from the magic angle of 1.10 ± 0.05 degrees. Upon extinction of the insulating orders, the vacated phase space is taken over by superconducting domes that feature critical temperatures comparable to those in devices with strong insulators. In addition, we find that insulators at half-filling can reappear in small out-of-plane magnetic fields of 0.4 tesla, giving rise to quantized Hall states with a Chern number of 2. Our study suggests re-examination of the often-assumed 'parent-and-child' relation between the insulating and superconducting phases in moiré graphene, and suggests a way of directly probing the microscopic mechanisms of superconductivity in strongly correlated systems.

8.
N Engl J Med ; 387(18): 1661-1672, 2022 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-36322845

RESUMO

BACKGROUND: Whether higher parenteral amino acid intake improves outcomes in infants with extremely low birth weight is unclear. METHODS: In this multicenter, parallel-group, double-blind, randomized, placebo-controlled trial, we assigned infants with birth weights of less than 1000 g at 8 neonatal intensive care units to receive amino acids at a dose of 1 g per day (intervention group) or placebo in addition to usual nutrition for the first 5 days after birth. The primary outcome was survival free from neurodisability as assessed with the Bayley Scales of Infant and Toddler Development and neurologic examination at 2 years, corrected for gestational age at birth. Secondary outcomes were the components of the primary outcome as well as the presence or absence of neonatal disorders, the rate of growth, and nutritional intake. RESULTS: We enrolled 434 infants (217 per group) in this trial. Survival free from neurodisability was observed in 97 of 203 children (47.8%) in the intervention group and in 102 of 205 (49.8%) in the placebo group (adjusted relative risk, 0.95; 95% confidence interval [CI], 0.79 to 1.14; P = 0.56). Death before the age of 2 years occurred in 39 of 217 children (18.0%) in the intervention group and 42 of 217 (19.4%) in the placebo group (adjusted relative risk, 0.93; 95% CI, 0.63 to 1.36); neurodisability occurred in 67 of 164 children (40.9%) in the intervention group and 61 of 163 (37.4%) in the placebo group (adjusted relative risk, 1.16; 95% CI, 0.90 to 1.50). Neurodisability was moderate to severe in 27 children (16.5%) in the intervention group and 14 (8.6%) in the placebo group (adjusted relative risk, 1.95; 95% CI, 1.09 to 3.48). More children in the intervention group than in the placebo group had patent ductus arteriosus (adjusted relative risk, 1.65; 95% CI, 1.11 to 2.46). In a post hoc analysis, refeeding syndrome occurred in 42 of 172 children in the intervention group and 26 of 166 in the placebo group (adjusted relative risk, 1.64; 95% CI, 1.09 to 2.47). Eight serious adverse events occurred. CONCLUSIONS: In infants with extremely low birth weight, extra parenteral amino acids at a dose of 1 g per day for 5 days after birth did not increase the number who survived free from neurodisability at 2 years. (Funded by the New Zealand Health Research Council and others; ProVIDe Australian New Zealand Clinical Trials Registry number, ACTRN12612001084875.).


Assuntos
Aminoácidos , Recém-Nascido de Peso Extremamente Baixo ao Nascer , Lactente Extremamente Prematuro , Doenças do Sistema Nervoso , Transtornos do Neurodesenvolvimento , Pré-Escolar , Humanos , Lactente , Recém-Nascido , Aminoácidos/administração & dosagem , Aminoácidos/efeitos adversos , Aminoácidos/uso terapêutico , Austrália , Permeabilidade do Canal Arterial/etiologia , Método Duplo-Cego , Nutrição Parenteral/métodos , Terapia Intensiva Neonatal , Transtornos do Neurodesenvolvimento/diagnóstico , Transtornos do Neurodesenvolvimento/etiologia , Transtornos do Neurodesenvolvimento/prevenção & controle , Doenças do Sistema Nervoso/diagnóstico , Doenças do Sistema Nervoso/etiologia , Doenças do Sistema Nervoso/prevenção & controle
9.
Nat Mater ; 23(4): 499-505, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38321241

RESUMO

Compressing light into nanocavities substantially enhances light-matter interactions, which has been a major driver for nanostructured materials research. However, extreme confinement generally comes at the cost of absorption and low resonator quality factors. Here we suggest an alternative optical multimodal confinement mechanism, unlocking the potential of hyperbolic phonon polaritons in isotopically pure hexagonal boron nitride. We produce deep-subwavelength cavities and demonstrate several orders of magnitude improvement in confinement, with estimated Purcell factors exceeding 108 and quality factors in the 50-480 range, values approaching the intrinsic quality factor of hexagonal boron nitride polaritons. Intriguingly, the quality factors we obtain exceed the maximum predicted by impedance-mismatch considerations, indicating that confinement is boosted by higher-order modes. We expect that our multimodal approach to nanoscale polariton manipulation will have far-reaching implications for ultrastrong light-matter interactions, mid-infrared nonlinear optics and nanoscale sensors.

10.
Arterioscler Thromb Vasc Biol ; 44(6): 1318-1329, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38634281

RESUMO

BACKGROUND: Tissue resident memory T (TRM) cells are a T-cell subset that resides at the site of prior antigen recognition to protect the body against reoccurring encounters. Besides their protective function, TRM cells have also been implicated in inflammatory disorders. TRM cells are characterized by the expression of CD69 and transcription factors Hobit (homolog of Blimp-1 [B lymphocyte-induced maturation protein 1] in T cells) and Blimp-1. As the majority of T cells in the arterial intima expresses CD69, TRM cells may contribute to the pathogenesis of atherosclerosis as well. Here, we aimed to assess the presence and potential role of TRM cells in atherosclerosis. METHODS: To identify TRM cells in human atherosclerotic lesions, a single-cell RNA-sequencing data set was interrogated, and T-cell phenotypes were compared with that of integrated predefined TRM cells. The presence and phenotype of TRM in atherosclerotic lesions was corroborated using a mouse model that enabled tracking of Hobit-expressing TRM cells. To explore the function of TRM cells during atherogenesis, RAG1-/- (recombination activating gene 1 deficient) LDLr-/- (low-density lipoprotein receptor knockout) mice received a bone marrow transplant from HobitKO/CREBlimp-1flox/flox mice, which exhibit abrogated TRM cell formation, whereafter the mice were fed a Western-type diet for 10 weeks. RESULTS: Human atherosclerotic lesions contained T cells that exhibited a TRM cell-associated gene signature. Moreover, a fraction of these T cells clustered together with predefined TRM cells upon integration. The presence of Hobit-expressing TRM cells in the atherosclerotic lesion was confirmed in mice. These lesion-derived TRM cells were characterized by the expression of CD69 and CD49α. Moreover, we demonstrated that this small T-cell subset significantly affects lesion composition, by reducing the amount of intralesional macrophages and increasing collagen content. CONCLUSIONS: TRM cells, characterized by the expression of CD69 and CD49α, constitute a minor population in atherosclerotic lesions and are associated with increased lesion stability in a Hobit and Blimp-1 knockout mouse model.


Assuntos
Aterosclerose , Modelos Animais de Doenças , Memória Imunológica , Macrófagos , Células T de Memória , Camundongos Endogâmicos C57BL , Placa Aterosclerótica , Receptores de LDL , Animais , Aterosclerose/patologia , Aterosclerose/imunologia , Aterosclerose/metabolismo , Aterosclerose/genética , Humanos , Células T de Memória/imunologia , Células T de Memória/metabolismo , Macrófagos/metabolismo , Macrófagos/imunologia , Macrófagos/patologia , Receptores de LDL/genética , Receptores de LDL/deficiência , Camundongos , Masculino , Camundongos Knockout , Antígenos de Diferenciação de Linfócitos T/metabolismo , Antígenos de Diferenciação de Linfócitos T/genética , Lectinas Tipo C/metabolismo , Lectinas Tipo C/genética , Fenótipo , Feminino , Antígenos CD/metabolismo , Antígenos CD/genética , Doenças da Aorta/patologia , Doenças da Aorta/imunologia , Doenças da Aorta/genética , Doenças da Aorta/metabolismo
11.
Arterioscler Thromb Vasc Biol ; 44(6): 1302-1314, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38511327

RESUMO

INTRODUCTION: Viral infections have been associated with the progression of atherosclerosis and CD8+ T-cells directed against common viruses, such as influenza, Epstein-Barr virus, and cytomegalovirus, have been detected inside human atherosclerotic lesions. These virus-specific CD8+ T-cells have been hypothesized to contribute to the development of atherosclerosis; however, whether they affect disease progression directly remains unclear. In this study, we aimed to characterize the activation status of virus-specific CD8+ T-cells in the atherosclerotic lesion. METHODS: The presence, clonality, tissue enrichment, and phenotype of virus-associated CD8+ T-cells in atherosclerotic lesions were assessed by exploiting bulk T-cell receptor-ß sequencing and single-cell T-cell receptor (α and ß) sequencing datasets on human endarterectomy samples and patient-matched blood samples. To investigate if virus-specific CD8+ T-cells can be activated through T-cell receptor stimulation in the atherosclerotic lesion, the immunopeptidome of human plaques was determined. RESULTS: Virus-associated CD8+ T-cells accumulated more in the atherosclerotic lesion (mean=2.0%), compared with patient-matched blood samples (mean=1.4%; P=0.05), and were more clonally expanded and tissue enriched in the atherosclerotic lesion in comparison with nonassociated CD8+ T-cells from the lesion. Single-cell T-cell receptor sequencing and flow cytometry revealed that these virus-associated CD8+ T-cells were phenotypically highly similar to other CD8+ T-cells in the lesion and that both exhibited a more activated phenotype compared with circulating T-cells. Interestingly, virus-associated CD8+ T-cells are unlikely to be activated through antigen-specific interactions in the atherosclerotic lesion, as no virus-derived peptides were detected on HLA-I in the lesion. CONCLUSIONS: This study suggests that virus-specific CD8+ T-cells are tissue enriched in atherosclerotic lesions; however, their potential contribution to inflammation may involve antigen-independent mechanisms.


Assuntos
Linfócitos T CD8-Positivos , Ativação Linfocitária , Placa Aterosclerótica , Humanos , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/virologia , Aterosclerose/imunologia , Aterosclerose/virologia , Aterosclerose/patologia , Masculino , Fenótipo , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Receptores de Antígenos de Linfócitos T alfa-beta/metabolismo , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Feminino , Pessoa de Meia-Idade , Idoso , Doenças das Artérias Carótidas/imunologia , Doenças das Artérias Carótidas/virologia , Doenças das Artérias Carótidas/patologia , Interações Hospedeiro-Patógeno
12.
Arterioscler Thromb Vasc Biol ; 44(6): 1346-1364, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38660806

RESUMO

BACKGROUND: Atherosclerosis is the major underlying pathology of cardiovascular disease and is driven by dyslipidemia and inflammation. Inhibition of the immunoproteasome, a proteasome variant that is predominantly expressed by immune cells and plays an important role in antigen presentation, has been shown to have immunosuppressive effects. METHODS: We assessed the effect of ONX-0914, an inhibitor of the immunoproteasomal catalytic subunits LMP7 (proteasome subunit ß5i/large multifunctional peptidase 7) and LMP2 (proteasome subunit ß1i/large multifunctional peptidase 2), on atherosclerosis and metabolism in LDLr-/- and APOE*3-Leiden.CETP mice. RESULTS: ONX-0914 treatment significantly reduced atherosclerosis, reduced dendritic cell and macrophage levels and their activation, as well as the levels of antigen-experienced T cells during early plaque formation, and Th1 cells in advanced atherosclerosis in young and aged mice in various immune compartments. Additionally, ONX-0914 treatment led to a strong reduction in white adipose tissue mass and adipocyte progenitors, which coincided with neutrophil and macrophage accumulation in white adipose tissue. ONX-0914 reduced intestinal triglyceride uptake and gastric emptying, likely contributing to the reduction in white adipose tissue mass, as ONX-0914 did not increase energy expenditure or reduce total food intake. Concomitant with the reduction in white adipose tissue mass upon ONX-0914 treatment, we observed improvements in markers of metabolic syndrome, including lowered plasma triglyceride levels, insulin levels, and fasting blood glucose. CONCLUSIONS: We propose that immunoproteasomal inhibition reduces 3 major causes underlying cardiovascular disease, dyslipidemia, metabolic syndrome, and inflammation and is a new target in drug development for atherosclerosis treatment.


Assuntos
Tecido Adiposo Branco , Aterosclerose , Modelos Animais de Doenças , Síndrome Metabólica , Camundongos Endogâmicos C57BL , Complexo de Endopeptidases do Proteassoma , Receptores de LDL , Animais , Aterosclerose/patologia , Aterosclerose/prevenção & controle , Aterosclerose/tratamento farmacológico , Aterosclerose/imunologia , Aterosclerose/genética , Aterosclerose/metabolismo , Síndrome Metabólica/tratamento farmacológico , Síndrome Metabólica/imunologia , Tecido Adiposo Branco/metabolismo , Tecido Adiposo Branco/efeitos dos fármacos , Tecido Adiposo Branco/patologia , Receptores de LDL/genética , Receptores de LDL/deficiência , Complexo de Endopeptidases do Proteassoma/metabolismo , Masculino , Inibidores de Proteassoma/farmacologia , Apolipoproteína E3/genética , Apolipoproteína E3/metabolismo , Doenças da Aorta/prevenção & controle , Doenças da Aorta/patologia , Doenças da Aorta/genética , Doenças da Aorta/enzimologia , Doenças da Aorta/imunologia , Doenças da Aorta/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Macrófagos/imunologia , Placa Aterosclerótica , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Camundongos Knockout para ApoE , Camundongos , Metabolismo Energético/efeitos dos fármacos , Oligopeptídeos
13.
Chem Rev ; 123(16): 9720-9785, 2023 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-37459506

RESUMO

Endogenous photosensitizers play a critical role in both beneficial and harmful light-induced transformations in biological systems. Understanding their mode of action is essential for advancing fields such as photomedicine, photoredox catalysis, environmental science, and the development of sun care products. This review offers a comprehensive analysis of endogenous photosensitizers in human skin, investigating the connections between their electronic excitation and the subsequent activation or damage of organic biomolecules. We gather the physicochemical and photochemical properties of key endogenous photosensitizers and examine the relationships between their chemical reactivity, location within the skin, and the primary biochemical events following solar radiation exposure, along with their influence on skin physiology and pathology. An important take-home message of this review is that photosensitization allows visible light and UV-A radiation to have large effects on skin. The analysis presented here unveils potential causes for the continuous increase in global skin cancer cases and emphasizes the limitations of current sun protection approaches.


Assuntos
Fármacos Fotossensibilizantes , Neoplasias Cutâneas , Humanos , Pele/efeitos da radiação , Neoplasias Cutâneas/etiologia , Neoplasias Cutâneas/prevenção & controle , Raios Ultravioleta , Luz
14.
Brain ; 147(6): 2203-2213, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38797521

RESUMO

Stuttering affects approximately 1 in 100 adults and can result in significant communication problems and social anxiety. It most often occurs as a developmental disorder but can also be caused by focal brain damage. These latter cases may lend unique insight into the brain regions causing stuttering. Here, we investigated the neuroanatomical substrate of stuttering using three independent datasets: (i) case reports from the published literature of acquired neurogenic stuttering following stroke (n = 20, 14 males/six females, 16-77 years); (ii) a clinical single study cohort with acquired neurogenic stuttering following stroke (n = 20, 13 males/seven females, 45-87 years); and (iii) adults with persistent developmental stuttering (n = 20, 14 males/six females, 18-43 years). We used the first two datasets and lesion network mapping to test whether lesions causing acquired stuttering map to a common brain network. We then used the third dataset to test whether this lesion-based network was relevant to developmental stuttering. In our literature dataset, we found that lesions causing stuttering occurred in multiple heterogeneous brain regions, but these lesion locations were all functionally connected to a common network centred around the left putamen, including the claustrum, amygdalostriatal transition area and other adjacent areas. This finding was shown to be specific for stuttering (PFWE < 0.05) and reproducible in our independent clinical cohort of patients with stroke-induced stuttering (PFWE < 0.05), resulting in a common acquired stuttering network across both stroke datasets. Within the common acquired stuttering network, we found a significant association between grey matter volume and stuttering impact for adults with persistent developmental stuttering in the left posteroventral putamen, extending into the adjacent claustrum and amygdalostriatal transition area (PFWE < 0.05). We conclude that lesions causing acquired neurogenic stuttering map to a common brain network, centred to the left putamen, claustrum and amygdalostriatal transition area. The association of this lesion-based network with symptom severity in developmental stuttering suggests a shared neuroanatomy across aetiologies.


Assuntos
Encéfalo , Acidente Vascular Cerebral , Gagueira , Humanos , Gagueira/patologia , Gagueira/etiologia , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Adolescente , Idoso , Idoso de 80 Anos ou mais , Adulto Jovem , Encéfalo/patologia , Encéfalo/diagnóstico por imagem , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/patologia , Imageamento por Ressonância Magnética , Mapeamento Encefálico/métodos
15.
Nature ; 573(7775): 507-518, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31554977

RESUMO

The development of silicon semiconductor technology has produced breakthroughs in electronics-from the microprocessor in the late 1960s to early 1970s, to automation, computers and smartphones-by downscaling the physical size of devices and wires to the nanometre regime. Now, graphene and related two-dimensional (2D) materials offer prospects of unprecedented advances in device performance at the atomic limit, and a synergistic combination of 2D materials with silicon chips promises a heterogeneous platform to deliver massively enhanced potential based on silicon technology. Integration is achieved via three-dimensional monolithic construction of multifunctional high-rise 2D silicon chips, enabling enhanced performance by exploiting the vertical direction and the functional diversification of the silicon platform for applications in opto-electronics and sensing. Here we review the opportunities, progress and challenges of integrating atomically thin materials with silicon-based nanosystems, and also consider the prospects for computational and non-computational applications.

16.
Proc Natl Acad Sci U S A ; 119(21): e2202012119, 2022 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-35588457

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS­CoV-2) is a worldwide health concern, and new treatment strategies are needed. Targeting inflammatory innate immunity pathways holds therapeutic promise, but effective molecular targets remain elusive. Here, we show that human caspase-4 (CASP4) and its mouse homolog, caspase-11 (CASP11), are up-regulated in SARS­CoV-2 infections and that CASP4 expression correlates with severity of SARS­CoV-2 infection in humans. SARS­CoV-2­infected Casp11−/− mice were protected from severe weight loss and lung pathology, including blood vessel damage, compared to wild-type (WT) mice and mice lacking the caspase downstream effector gasdermin-D (Gsdmd−/−). Notably, viral titers were similar regardless of CASP11 knockout. Global transcriptomics of SARS­CoV-2­infected WT, Casp11−/−, and Gsdmd−/− lungs identified restrained expression of inflammatory molecules and altered neutrophil gene signatures in Casp11−/− mice. We confirmed that protein levels of inflammatory mediators interleukin (IL)-1ß, IL-6, and CXCL1, as well as neutrophil functions, were reduced in Casp11−/− lungs. Additionally, Casp11−/− lungs accumulated less von Willebrand factor, a marker for endothelial damage, but expressed more Kruppel-Like Factor 2, a transcription factor that maintains vascular integrity. Overall, our results demonstrate that CASP4/11 promotes detrimental SARS­CoV-2­induced inflammation and coagulopathy, largely independently of GSDMD, identifying CASP4/11 as a promising drug target for treatment and prevention of severe COVID-19.


Assuntos
COVID-19 , Caspases Iniciadoras/metabolismo , SARS-CoV-2 , Tromboinflamação , Animais , COVID-19/enzimologia , COVID-19/patologia , Caspases Iniciadoras/genética , Progressão da Doença , Humanos , Pulmão/patologia , Camundongos , Camundongos Knockout , Índice de Gravidade de Doença , Tromboinflamação/enzimologia , Tromboinflamação/genética
17.
Nano Lett ; 24(12): 3678-3685, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38471109

RESUMO

Control over the optical properties of atomically thin two-dimensional (2D) layers, including those of transition metal dichalcogenides (TMDs), is needed for future optoelectronic applications. Here, the near-field coupling between TMDs and graphene/graphite is used to engineer the exciton line shape and charge state. Fano-like asymmetric spectral features are produced in WS2, MoSe2, and WSe2 van der Waals heterostructures combined with graphene, graphite, or jointly with hexagonal boron nitride (h-BN) as supporting or encapsulating layers. Furthermore, trion emission is suppressed in h-BN encapsulated WSe2/graphene with a neutral exciton red shift (44 meV) and binding energy reduction (30 meV). The response of these systems to electron beam and light probes is well-described in terms of 2D optical conductivities of the involved materials. Beyond fundamental insights into the interaction of TMD excitons with structured environments, this study opens an unexplored avenue toward shaping the spectral profile of narrow optical modes for application in nanophotonic devices.

18.
Gut ; 73(5): 741-750, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38216328

RESUMO

OBJECTIVE: Endoscopic mucosal resection (EMR) is the preferred treatment for non-invasive large (≥20 mm) non-pedunculated colorectal polyps (LNPCPs) but is associated with an early recurrence rate of up to 30%. We evaluated whether standardised EMR training could reduce recurrence rates in Dutch community hospitals. DESIGN: In this multicentre cluster randomised trial, 59 endoscopists from 30 hospitals were randomly assigned to the intervention group (e-learning and 2-day training including hands-on session) or control group. From April 2019 to August 2021, all consecutive EMR-treated LNPCPs were included. Primary endpoint was recurrence rate after 6 months. RESULTS: A total of 1412 LNPCPs were included; 699 in the intervention group and 713 in the control group (median size 30 mm vs 30 mm, 45% vs 52% size, morphology, site and access (SMSA) score IV, 64% vs 64% proximal location). Recurrence rates were lower in the intervention group compared with controls (13% vs 25%, OR 0.43; 95% CI 0.23 to 0.78; p=0.005) with similar complication rates (8% vs 9%, OR 0.93; 95% CI 0.64 to 1.36; p=0.720). Recurrences were more often unifocal in the intervention group (92% vs 76%; p=0.006). In sensitivity analysis, the benefit of the intervention on recurrence rate was only observed in the 20-40 mm LNPCPs (5% vs 20% in 20-29 mm, p=0.001; 10% vs 21% in 30-39 mm, p=0.013) but less evident in ≥40 mm LNPCPs (24% vs 31%; p=0.151). In a post hoc analysis, the training effect was maintained in the study group, while in the control group the recurrence rate remained high. CONCLUSION: A compact standardised EMR training for LNPCPs significantly reduced recurrences in community hospitals. This strongly argues for a national dedicated training programme for endoscopists performing EMR of ≥20 mm LNPCPs. Interestingly, in sensitivity analysis, this benefit was limited for LNPCPs ≥40 mm. TRIAL REGISTRATION NUMBER: NTR7477.


Assuntos
Pólipos do Colo , Neoplasias Colorretais , Ressecção Endoscópica de Mucosa , Humanos , Pólipos do Colo/cirurgia , Colonoscopia , Neoplasias Colorretais/cirurgia
19.
J Neurosci ; 43(42): 7028-7040, 2023 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-37669861

RESUMO

Parkinson's disease (PD) and progressive supranuclear palsy (PSP) both impair response inhibition, exacerbating impulsivity. Inhibitory control deficits vary across individuals and are linked with worse prognosis, and lack improvement on dopaminergic therapy. Motor and cognitive control are associated with noradrenergic innervation of the cortex, arising from the locus coeruleus (LC) noradrenergic system. Here we test the hypothesis that structural variation of the LC explains response inhibition deficits in PSP and PD. Twenty-four people with idiopathic PD, 14 with PSP-Richardson's syndrome, and 24 age- and sex-matched controls undertook a stop-signal task and ultrahigh field 7T magnetization-transfer-weighted imaging of the LC. Parameters of "race models" of go- versus stop-decisions were estimated using hierarchical Bayesian methods to quantify the cognitive processes of response inhibition. We tested the multivariate relationship between LC integrity and model parameters using partial least squares. Both disorders impaired response inhibition at the group level. PSP caused a distinct pattern of abnormalities in inhibitory control with a paradoxically reduced threshold for go responses, but longer nondecision times, and more lapses of attention. The variation in response inhibition correlated with the variability of LC integrity across participants in both clinical groups. Structural imaging of the LC, coupled with behavioral modeling in parkinsonian disorders, confirms that LC integrity is associated with response inhibition and LC degeneration contributes to neurobehavioral changes. The noradrenergic system is therefore a promising target to treat impulsivity in these conditions. The optimization of noradrenergic treatment is likely to benefit from stratification according to LC integrity.SIGNIFICANCE STATEMENT Response inhibition deficits contribute to clinical symptoms and poor outcomes in people with Parkinson's disease and progressive supranuclear palsy. We used cognitive modeling of performance of a response inhibition task to identify disease-specific mechanisms of abnormal inhibitory control. Response inhibition in both patient groups was associated with the integrity of the noradrenergic locus coeruleus, which we measured in vivo using ultra-high field MRI. We propose that the imaging biomarker of locus coeruleus integrity provides a trans-diagnostic tool to explain individual differences in response inhibition ability beyond the classic nosological borders and diagnostic criteria. Our data suggest a potential new stratified treatment approach for Parkinson's disease and progressive supranuclear palsy.


Assuntos
Doença de Parkinson , Transtornos Parkinsonianos , Paralisia Supranuclear Progressiva , Humanos , Paralisia Supranuclear Progressiva/diagnóstico por imagem , Paralisia Supranuclear Progressiva/psicologia , Doença de Parkinson/complicações , Doença de Parkinson/diagnóstico por imagem , Locus Cerúleo , Teorema de Bayes
20.
Infect Immun ; : e0013324, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38953668

RESUMO

Staphylococcus aureus α-hemolysin (Hla) is a pore-forming toxin critical for the pathogenesis of skin and soft tissue infections, which causes the pathognomonic lesion of cutaneous necrosis (dermonecrosis) in mouse models. To determine the mechanism by which dermonecrosis develops during S. aureus skin infection, mice were given control serum, Hla-neutralizing antiserum, or an inhibitor of Hla receptor [A-disintegrin and metalloprotease 10 (ADAM10) inhibitor] followed by subcutaneous infection by S. aureus, and the lesions were evaluated using immunohistochemistry and immunofluorescence. Hla induced apoptosis in the vascular endothelium at 6 hours post-infection (hpi), followed by apoptosis in keratinocytes at 24 hpi. The loss of vascular endothelial (VE)-cadherin expression preceded the loss of epithelial-cadherin expression. Hla also induced hypoxia in the keratinocytes at 24 hpi following vascular injury. Treatment with Hla-neutralizing antibody or ADAM10 inhibitor attenuated early cleavage of VE-cadherin, cutaneous hypoxia, and dermonecrosis. These findings suggest that Hla-mediated vascular injury with cutaneous hypoxia underlies the pathogenesis of S. aureus-induced dermonecrosis.

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