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1.
N Engl J Med ; 389(22): 2063-2075, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-37861218

RESUMO

BACKGROUND: Tarlatamab, a bispecific T-cell engager immunotherapy targeting delta-like ligand 3 and CD3, showed promising antitumor activity in a phase 1 trial in patients with previously treated small-cell lung cancer. METHODS: In this phase 2 trial, we evaluated the antitumor activity and safety of tarlatamab, administered intravenously every 2 weeks at a dose of 10 mg or 100 mg, in patients with previously treated small-cell lung cancer. The primary end point was objective response (complete or partial response), as assessed by blinded independent central review according to the Response Evaluation Criteria in Solid Tumors, version 1.1. RESULTS: Overall, 220 patients received tarlatamab; patients had previously received a median of two lines of treatment. Among patients evaluated for antitumor activity and survival, the median follow-up was 10.6 months in the 10-mg group and 10.3 months in the 100-mg group. An objective response occurred in 40% (97.5% confidence interval [CI], 29 to 52) of the patients in the 10-mg group and in 32% (97.5% CI, 21 to 44) of those in the 100-mg group. Among patients with an objective response, the duration of response was at least 6 months in 59% (40 of 68 patients). Objective responses at the time of data cutoff were ongoing in 22 of 40 patients (55%) in the 10-mg group and in 16 of 28 patients (57%) in the 100-mg group. The median progression-free survival was 4.9 months (95% CI, 2.9 to 6.7) in the 10-mg group and 3.9 months (95% CI, 2.6 to 4.4) in the 100-mg group; the estimates of overall survival at 9 months were 68% and 66% of patients, respectively. The most common adverse events were cytokine-release syndrome (in 51% of the patients in the 10-mg group and in 61% of those in the 100-mg group), decreased appetite (in 29% and 44%, respectively), and pyrexia (in 35% and 33%). Cytokine-release syndrome occurred primarily during treatment cycle 1, and events in most of the patients were grade 1 or 2 in severity. Grade 3 cytokine-release syndrome occurred less frequently in the 10-mg group (in 1% of the patients) than in the 100-mg group (in 6%). A low percentage of patients (3%) discontinued tarlatamab because of treatment-related adverse events. CONCLUSIONS: Tarlatamab, administered as a 10-mg dose every 2 weeks, showed antitumor activity with durable objective responses and promising survival outcomes in patients with previously treated small-cell lung cancer. No new safety signals were identified. (Funded by Amgen; DeLLphi-301 ClinicalTrials.gov number, NCT05060016.).


Assuntos
Antineoplásicos Imunológicos , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Carcinoma de Pequenas Células do Pulmão , Humanos , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Citocinas , Neoplasias Pulmonares/tratamento farmacológico , Carcinoma de Pequenas Células do Pulmão/tratamento farmacológico , Antineoplásicos Imunológicos/administração & dosagem , Antineoplásicos Imunológicos/efeitos adversos , Antineoplásicos Imunológicos/uso terapêutico , Administração Intravenosa , Síndrome da Liberação de Citocina/induzido quimicamente , Síndrome da Liberação de Citocina/etiologia
2.
Blood ; 144(13): 1399-1411, 2024 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-38968149

RESUMO

ABSTRACT: B-cell progenitor acute lymphoblastic leukemia (BCP-ALL) is the most common childhood malignancy and is driven by multiple genetic alterations that cause maturation arrest and accumulation of abnormal progenitor B cells. Current treatment protocols with chemotherapy have led to favorable outcomes but are associated with significant toxicity and risk of side effects, highlighting the necessity for highly effective, less toxic, targeted drugs, even in subtypes with a favorable outcome. Here, we used multimodal single-cell sequencing to delineate the transcriptional, epigenetic, and immunophenotypic characteristics of 23 childhood BCP-ALLs belonging to the BCR::ABL1+, ETV6::RUNX1+, high hyperdiploid, and recently discovered DUX4-rearranged (DUX4-r) subtypes. Projection of the ALL cells along the normal hematopoietic differentiation axis revealed a diversity in the maturation pattern between the different BCP-ALL subtypes. Although the BCR::ABL1+, ETV6::RUNX1+, and high hyperdiploidy cells mainly showed similarities to normal pro-B cells, DUX4-r ALL cells also displayed transcriptional signatures resembling mature B cells. Focusing on the DUX4-r subtype, we found that the blast population displayed not only multilineage priming toward nonhematopoietic cells, myeloid, and T-cell lineages, but also an activation of phosphatidylinositol 3-kinase (PI3K)/AKT signaling that sensitized the cells to PI3K inhibition in vivo. Given the multilineage priming of DUX4-r blasts with aberrant expression of myeloid marker CD371 (CLL-1), we generated chimeric antigen receptor T cells, which effectively eliminated DUX4-r ALL cells in vivo. These results provide a detailed characterization of BCP-ALL at the single-cell level and reveal therapeutic vulnerabilities in the DUX4-r subtype, with implications for the understanding of ALL biology and new therapeutic strategies.


Assuntos
Genômica , Proteínas de Homeodomínio , Leucemia-Linfoma Linfoblástico de Células Precursoras B , Análise de Célula Única , Humanos , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras B/patologia , Leucemia-Linfoma Linfoblástico de Células Precursoras B/terapia , Leucemia-Linfoma Linfoblástico de Células Precursoras B/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras B/tratamento farmacológico , Genômica/métodos , Animais , Camundongos , Criança , Masculino , Feminino
3.
Plant Cell ; 35(5): 1496-1512, 2023 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-36753568

RESUMO

Cell divisions are accurately positioned to generate cells of the correct size and shape. In plant cells, the new cell wall is built in the middle of the cell by vesicles trafficked along an antiparallel microtubule and a microfilament array called the phragmoplast. The phragmoplast expands toward a specific location at the cell cortex called the division site, but how it accurately reaches the division site is unclear. We observed microtubule arrays that accumulate at the cell cortex during the telophase transition in maize (Zea mays) leaf epidermal cells. Before the phragmoplast reaches the cell cortex, these cortical-telophase microtubules transiently interact with the division site. Increased microtubule plus end capture and pausing occur when microtubules contact the division site-localized protein TANGLED1 or other closely associated proteins. Microtubule capture and pausing align the cortical microtubules perpendicular to the division site during telophase. Once the phragmoplast reaches the cell cortex, cortical-telophase microtubules are incorporated into the phragmoplast primarily by parallel bundling. The addition of microtubules into the phragmoplast promotes fine-tuning of the positioning at the division site. Our hypothesis is that division site-localized proteins such as TANGLED1 organize cortical microtubules during telophase to mediate phragmoplast positioning at the final division plane.


Assuntos
Arabidopsis , Zea mays , Zea mays/genética , Citocinese , Telófase , Microtúbulos/metabolismo , Mitose
4.
Proc Natl Acad Sci U S A ; 119(15): e2103745119, 2022 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-35377801

RESUMO

Body size and shape fundamentally determine organismal energy requirements by modulating heat and mass exchange with the environment and the costs of locomotion, thermoregulation, and maintenance. Ecologists have long used the physical linkage between morphology and energy balance to explain why the body size and shape of many organisms vary across climatic gradients, e.g., why larger endotherms are more common in colder regions. However, few modeling exercises have aimed at investigating this link from first principles. Body size evolution in bats contrasts with the patterns observed in other endotherms, probably because physical constraints on flight limit morphological adaptations. Here, we develop a biophysical model based on heat transfer and aerodynamic principles to investigate energy constraints on morphological evolution in bats. Our biophysical model predicts that the energy costs of thermoregulation and flight, respectively, impose upper and lower limits on the relationship of wing surface area to body mass (S-MR), giving rise to an optimal S-MR at which both energy costs are minimized. A comparative analysis of 278 species of bats supports the model's prediction that S-MR evolves toward an optimal shape and that the strength of selection is higher among species experiencing greater energy demands for thermoregulation in cold climates. Our study suggests that energy costs modulate the mode of morphological evolution in bats­hence shedding light on a long-standing debate over bats' conformity to ecogeographical patterns observed in other mammals­and offers a procedure for investigating complex macroecological patterns from first principles.


Assuntos
Regulação da Temperatura Corporal , Quirópteros , Voo Animal , Asas de Animais , Animais , Fenômenos Biofísicos , Tamanho Corporal , Quirópteros/anatomia & histologia , Quirópteros/fisiologia , Clima , Voo Animal/fisiologia , Asas de Animais/anatomia & histologia , Asas de Animais/fisiologia
5.
Proc Natl Acad Sci U S A ; 119(21): e2119483119, 2022 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-35588454

RESUMO

Chemokine receptor nanoscale organization at the cell membrane is orchestrated by the actin cytoskeleton and influences cell responses. Using single-particle tracking analysis we show that CXCR4R334X, a truncated mutant chemokine receptor linked to WHIM syndrome (warts, hypogammaglobulinemia, infections, myelokathexis), fails to nanoclusterize after CXCL12 stimulation, and alters the lateral mobility and spatial organization of CXCR4 when coexpressed. These findings correlate with multiple phalloidin-positive protrusions in cells expressing CXCR4R334X, and their inability to correctly sense chemokine gradients. The underlying mechanisms involve inappropriate actin cytoskeleton remodeling due to the inadequate ß-arrestin1 activation by CXCR4R334X, which disrupts the equilibrium between activated and deactivated cofilin. Overall, we provide insights into the molecular mechanisms governing CXCR4 nanoclustering, signaling and cell function, and highlight the essential scaffold role of ß-arrestin1 to support CXCL12-mediated actin reorganization and receptor clustering. These defects associated with CXCR4R334X expression might contribute to the severe immunological symptoms associated with WHIM syndrome.


Assuntos
Doenças da Imunodeficiência Primária , Receptores CXCR4 , Verrugas , Fatores de Despolimerização de Actina/metabolismo , Membrana Celular/metabolismo , Movimento Celular , Humanos , Mutação , Doenças da Imunodeficiência Primária/genética , Doenças da Imunodeficiência Primária/metabolismo , Receptores CXCR4/genética , Receptores CXCR4/metabolismo , Imagem Individual de Molécula , Verrugas/genética , Verrugas/metabolismo
6.
J Allergy Clin Immunol ; 154(3): 698-706, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38823490

RESUMO

BACKGROUND: In the recent years, there was an important improvement in the understanding of the pathogenesis of hereditary angioedema (HAE). Notwithstanding, in a large portion of patients with unknown mutation (HAE-UNK) the genetic cause remains to be identified. OBJECTIVES: To identify new genetic targets associated with HAE, a large Argentine family with HAE-UNK spanning 3 generations was studied. METHODS: Whole exome sequencing was performed on affected family members to identify potential genetic variants associated with HAE-UNK. In silico analyses and experimental studies were applied to assess the role of the identified gene variant. RESULTS: A missense variant (p.D239N) in DAB2IP was identified. The variant occurred in the C2-domain, the region interacting with vascular endothelial growth factor receptor 2 (VEGFR2). It was found to be rare, and predicted to have a detrimental effect on the functionality of DAB2IP. Protein structure modeling predicted changes in the mutant p.D239N protein structure, impacting protein stability. The p.D239N variant affected the subcellular localization of VEGFR2. Cells transfected with the DAB2IP-239N transcript exhibited an intracellular distribution, and VEGFR2 remained associated with the cell membrane. The altered localization pattern indicated reduced colocalization of the mutant protein with VEGFR2, suggesting a diminished ability of VEGFR2 binding. CONCLUSIONS: The study identified a novel missense variant (p.D239N) in DAB2IP in a family with HAE-UNK and highlighted the role of dysregulated VEGF-mediated signaling in altered endothelial permeability. DAB2IP loss-of-function pathogenic variants lead to the impairment of the endothelial VEGF/VEGFR2 ligand system and represent a new pathophysiologic cause of HAE-UNK.


Assuntos
Angioedemas Hereditários , Mutação de Sentido Incorreto , Linhagem , Transdução de Sinais , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Angioedemas Hereditários/genética , Angioedemas Hereditários/metabolismo , Sequenciamento do Exoma , Fator A de Crescimento do Endotélio Vascular/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
7.
Mol Med ; 30(1): 185, 2024 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-39455931

RESUMO

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease characterized by the loss of motoneurons (MNs), and despite progress, there is no effective treatment. A large body of evidence shows that astrocytes expressing ALS-linked mutant proteins cause non-cell autonomous toxicity of MNs. Although MNs innervate muscle fibers and ALS is characterized by the early disruption of the neuromuscular junction (NMJ) and axon degeneration, there are controversies about whether muscle contributes to non-cell-autonomous toxicity to MNs. In this study, we generated primary skeletal myotubes from myoblasts derived from ALS mice expressing human mutant SOD1G93A (termed hereafter mutSOD1). Characterization revealed that mutSOD1 skeletal myotubes display intrinsic phenotypic and functional differences compared to control myotubes generated from non-transgenic (NTg) littermates. Next, we analyzed whether ALS myotubes exert non-cell-autonomous toxicity to MNs. We report that conditioned media from mutSOD1 myotubes (mutSOD1-MCM), but not from control myotubes (NTg-MCM), induced robust death of primary MNs in mixed spinal cord cultures and compartmentalized microfluidic chambers. Our study further revealed that applying mutSOD1-MCM to the MN axonal side in microfluidic devices rapidly reduces mitochondrial axonal transport while increasing Ca2 + transients and reactive oxygen species (i.e., H2O2). These results indicate that soluble factor(s) released by mutSOD1 myotubes cause MN axonopathy that leads to lethal pathogenic changes.


Assuntos
Esclerose Lateral Amiotrófica , Transporte Axonal , Camundongos Transgênicos , Mitocôndrias , Neurônios Motores , Fibras Musculares Esqueléticas , Superóxido Dismutase-1 , Animais , Fibras Musculares Esqueléticas/metabolismo , Fibras Musculares Esqueléticas/patologia , Neurônios Motores/metabolismo , Neurônios Motores/patologia , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/metabolismo , Esclerose Lateral Amiotrófica/patologia , Mitocôndrias/metabolismo , Superóxido Dismutase-1/genética , Superóxido Dismutase-1/metabolismo , Camundongos , Humanos , Morte Celular , Modelos Animais de Doenças , Mutação , Células Cultivadas
8.
Oncologist ; 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39349396

RESUMO

BACKGROUND: The landscape of small cell lung cancer (SCLC) has changed since the 2019 and 2020 approvals of anti-PD-L1 atezolizumab and durvalumab for first-line (1L) treatment in combination with chemotherapy. We studied treatment patterns and real-world overall survival (rwOS) following 1L-3L therapy. PATIENTS AND METHODS: A nationwide electronic health record (EHR)-derived de-identified database was used to describe treatment patterns, characteristics, and survival of patients with extensive-stage (ES)-SCLC by 1L anti-PD-L1 treatment. Patients with ES-SCLC who initiated ≥1 line of systemic therapy from 2013 to 2021, with potential follow-up through 2022, were included. RESULTS: Among 9952 patients with SCLC, there were 4308 patients with ES-SCLC treated during the study period who met eligibility criteria. Etoposide + platinum (EP) chemotherapy was most common in the 1L, with addition of anti-PD-L1 therapy to most regimens by 2019. Second-line regimens varied by platinum sensitivity status and shifted from topotecan to lurbinectedin over time. Median rwOS following 1L therapy was 8.3 months (95% CI, 7.9-8.8) in those treated with 1L anti-PD-L1 and 8.0 months (95% CI, 7.8-8.2) in those who were not. Following 2L and 3L, median rwOS was 5.6 (95% CI, 4.9-6.3) and 4.9 months (95% CI, 3.4-6.0), respectively, among 1L anti-PD-L1-treated, and 4.5 (95% CI, 4.2-4.9) and 4.0 months (95% CI, 3.7-4.5), respectively, among those who were not. CONCLUSION: Despite the introduction of frontline anti-PD-L1 therapy, survival remains dismal among patients with ES-SCLC treated in the real-world setting.

9.
New Phytol ; 243(1): 162-179, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38706429

RESUMO

Some cyanobacteria can grow photoautotrophically or photomixotrophically by using simultaneously CO2 and glucose. The switch between these trophic modes and the role of glycogen, their main carbon storage macromolecule, was investigated. We analysed the effect of glucose addition on the physiology, metabolic and photosynthetic state of Synechocystis sp. PCC 6803 and mutants lacking phosphoglucomutase and ADP-glucose pyrophosphorylase, with limitations in glycogen synthesis. Glycogen acted as a metabolic buffer: glucose addition increased growth and glycogen reserves in the wild-type (WT), but arrested growth in the glycogen synthesis mutants. Already 30 min after glucose addition, metabolites from the Calvin-Benson-Bassham cycle and the oxidative pentose phosphate shunt increased threefold more in the glycogen synthesis mutants than the WT. These alterations substantially affected the photosynthetic performance of the glycogen synthesis mutants, as O2 evolution and CO2 uptake were both impaired. We conclude that glycogen synthesis is essential during transitions to photomixotrophy to avoid metabolic imbalance that induces inhibition of electron transfer from PSII and subsequently accumulation of reactive oxygen species, loss of PSII core proteins, and cell death. Our study lays foundations for optimising photomixotrophy-based biotechnologies through understanding the coordination of the crosstalk between photosynthetic electron transport and metabolism.


Assuntos
Glicogênio , Fotossíntese , Complexo de Proteína do Fotossistema II , Synechocystis , Synechocystis/metabolismo , Synechocystis/efeitos dos fármacos , Synechocystis/crescimento & desenvolvimento , Synechocystis/genética , Glicogênio/metabolismo , Transporte de Elétrons , Complexo de Proteína do Fotossistema II/metabolismo , Mutação/genética , Glucose/metabolismo , Dióxido de Carbono/metabolismo , Oxigênio/metabolismo , Glucose-1-Fosfato Adenililtransferase/metabolismo , Glucose-1-Fosfato Adenililtransferase/genética , Fosfoglucomutase/metabolismo , Fosfoglucomutase/genética
10.
Cardiovasc Diabetol ; 23(1): 361, 2024 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-39402581

RESUMO

BACKGROUND: Increasing evidence supports the role of advanced glycation end products (AGEs) in atherosclerosis in both diabetic and non-diabetic patients, suggesting that therapeutic strategies targeting AGEs may offer potential benefits in this population. The Mediterranean diet is associated with improved biomarkers and anthropometric measurements related with atherosclerosis in addition to its ability to modulate AGE metabolism. Our aim was to determine whether the reduction in atherosclerosis progression (measured by changes in intima-media thickness of both common carotid arteries (IMT-CC)), observed after consumption of a Mediterranean diet compared to a low-fat diet, is associated with a modulation of circulating AGE levels in patients with coronary heart disease (CHD). METHODS: 1002 CHD patients were divided in: (1) Non-increased IMT-CC patients, whose IMT-CC was reduced or not changed after dietary intervention and (2) Increased IMT-CC patients, whose IMT-CC was increased after dietary intervention. Serum AGE levels (methylglyoxal-MG and Nε-Carboxymethyllysine-CML) and parameters related to AGE metabolism (AGER1 and GloxI mRNA and sRAGE levels) and reduced glutathione (GSH) levels were measured before and after 5-years of dietary intervention. RESULTS: The Mediterranean diet did not affect MG levels, whereas the low-fat diet significantly increased them compared to baseline (p = 0.029), leading to lower MG levels following the Mediterranean diet than the low-fat diet (p < 0.001). The Mediterranean diet, but not the low-fat diet, produced an upregulation of AGE metabolism, with increased AGER1 and GloxI gene expression as well as increased GSH and sRAGE levels in Non-increased IMT-CC patients (all p < 0.05). Although the Mediterranean diet increased MG levels in Increased IMT-CC patients, this increment was lower compared to the low-fat diet (all p < 0.05). CONCLUSIONS: Our results suggest that an improvement in modulation of AGE metabolism, which facilitates better management of circulating AGE levels, may be one of the mechanisms through which the Mediterranean diet, compared to a low-fat diet, reduces the progression of atherosclerosis in patients with CHD. Trial registration https://clinicaltrials.gov/ct2/show/NCT00924937 , Clinicaltrials.gov number, NCT00924937.


Assuntos
Biomarcadores , Artéria Carótida Primitiva , Espessura Intima-Media Carotídea , Dieta Mediterrânea , Produtos Finais de Glicação Avançada , Receptor para Produtos Finais de Glicação Avançada , Humanos , Produtos Finais de Glicação Avançada/sangue , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Receptor para Produtos Finais de Glicação Avançada/sangue , Biomarcadores/sangue , Artéria Carótida Primitiva/diagnóstico por imagem , Resultado do Tratamento , Dieta com Restrição de Gorduras , Doenças das Artérias Carótidas/sangue , Doenças das Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/dietoterapia , Fatores de Tempo , Progressão da Doença , Antígenos de Neoplasias , Lactoilglutationa Liase , Proteínas Quinases Ativadas por Mitógeno
11.
Cardiovasc Diabetol ; 23(1): 98, 2024 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-38493287

RESUMO

BACKGROUND: Telomere Length (TL), a marker of cellular aging, holds promise as a biomarker to elucidate the molecular mechanism of diabetes. This study aimed to investigate whether shorter telomeres are associated with a higher risk of type 2 diabetes mellitus (T2DM) incidence in patients with coronary heart disease; and to determine whether the most suitable dietary patterns, particularly a Mediterranean diet or a low-fat diet, can mitigate the development of diabetes in these patients after a follow-up period of five years. METHODS: The CORonary Diet Intervention with Olive oil and cardiovascular PREVention study (CORDIOPREV study) was a single-centre, randomised clinical trial done at the Reina Sofia University Hospital in Córdoba, Spain. Patients with established coronary heart disease (aged 20-75 years) were randomly assigned in a 1:1 ratio by the Andalusian School of Public Health to receive two healthy diets. Clinical investigators were masked to treatment assignment; participants were not. Quantitative-PCR was used to assess TL measurements. FINDINGS: 1002 patients (59.5 ± 8.7 years and 82.5% men) were enrolled into Mediterranean diet (n = 502) or a low-fat diet (n = 500) groups. In this analysis, we included all 462 patients who did not have T2DM at baseline. Among them, 107 patients developed T2DM after a median of 60 months. Cox regression analyses showed that patients at risk of short telomeres (TL < percentile 20th) are more likely to experience T2DM than those at no risk of short telomeres (HR 1.65, p-value 0.023). In terms of diet, patients at high risk of short telomeres had a higher risk of T2DM incidence after consuming a low-fat diet compared to patients at no risk of short telomeres (HR 2.43, 95CI% 1.26 to 4.69, p-value 0.008), while no differences were observed in the Mediterranean diet group. CONCLUSION: Patients with shorter TL presented a higher risk of developing T2DM. This association could be mitigated with a specific dietary pattern, in our case a Mediterranean diet, to prevent T2DM in patients with coronary heart disease. TRIAL REGISTRATION: Clinicaltrials.gov number NCT00924937.


Assuntos
Doenças Cardiovasculares , Doença das Coronárias , Diabetes Mellitus Tipo 2 , Dieta Mediterrânea , Feminino , Humanos , Masculino , Biomarcadores , Doenças Cardiovasculares/epidemiologia , Doença das Coronárias/diagnóstico , Doença das Coronárias/epidemiologia , Doença das Coronárias/genética , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/genética , Telômero , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso
12.
NMR Biomed ; : e5258, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39350507

RESUMO

This study aims to develop methods to design the complete magnetic system for a truly portable MRI scanner for neurological and musculoskeletal (MSK) applications, optimized for field homogeneity, field of view (FoV), and gradient performance compared to existing low-weight configurations. We explore optimal elliptic-bore Halbach configurations based on discrete arrays of permanent magnets. In this way, we seek to improve the field homogeneity and remove constraints to the extent of the gradient coils typical of Halbach magnets. Specifically, we have optimized a tightly packed distribution of magnetic Nd2Fe14B cubes with differential evolution algorithms and a second array of shimming magnets with interior point and differential evolution methods. We have also designed and constructed an elliptical set of gradient coils that extend over the whole magnet length, maximizing the distance between the lobe centers. These are optimized with a target field method minimizing a cost function that considers also heat dissipation. We have employed the new toolbox to build the main magnet and gradient modules for a portable MRI scanner designed for point-of-care and residential use. The elliptical Halbach bore has semi-axes of 10 and 14& cm, and the magnet generates a field of 87& mT homogeneous down to 5700& ppm (parts per million) in a 20-cm diameter FoV; it weighs 216& kg and has a width of 65& cm and a height of 72& cm. Gradient efficiencies go up to around 0.8& mT/m/A, for a maximum of 12& mT/m within 0.5& ms with 15& A and 15& V amplifier. The distance between lobes is 28& cm, significantly increased with respect to other Halbach-based scanners. Heat dissipation is around 25& W at maximum power, and gradient deviations from linearity are below 20% in a 20-cm sphere. Elliptic-bore Halbach magnets enhance the ergonomicity and field distribution of low-cost portable MRI scanners, while allowing for full-length gradient support to increase the FoV. This geometry can be potentially adapted for a prospective low-cost whole-body technology.

13.
Acta Neuropathol ; 148(1): 15, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39102080

RESUMO

Asymptomatic Alzheimer's disease (AsymAD) describes the status of individuals with preserved cognition but identifiable Alzheimer's disease (AD) brain pathology (i.e., beta-amyloid (Aß) deposits, neuritic plaques, and neurofibrillary tangles) at autopsy. In this study, we investigated the postmortem brains of a cohort of AsymAD subjects to gain insight into the mechanisms underlying resilience to AD pathology and cognitive decline. Our results showed that AsymAD cases exhibit enrichment in core plaques, decreased filamentous plaque accumulation, and increased plaque-surrounding microglia. Less pathological tau aggregation in dystrophic neurites was found in AsymAD brains than in AD brains, and tau seeding activity was comparable to that in healthy brains. We used spatial transcriptomics to characterize the plaque niche further and revealed autophagy, endocytosis, and phagocytosis as the pathways associated with the genes upregulated in the AsymAD plaque niche. Furthermore, the levels of ARP2 and CAP1, which are actin-based motility proteins that participate in the dynamics of actin filaments to allow cell motility, were increased in the microglia surrounding amyloid plaques in AsymAD cases. Our findings suggest that the amyloid-plaque microenvironment in AsymAD cases is characterized by the presence of microglia with highly efficient actin-based cell motility mechanisms and decreased tau seeding compared with that in AD brains. These two mechanisms can potentially protect against the toxic cascade initiated by Aß, preserving brain health, and slowing AD pathology progression.


Assuntos
Doença de Alzheimer , Microglia , Placa Amiloide , Proteínas tau , Doença de Alzheimer/patologia , Doença de Alzheimer/metabolismo , Humanos , Microglia/metabolismo , Microglia/patologia , Placa Amiloide/patologia , Placa Amiloide/metabolismo , Proteínas tau/metabolismo , Idoso , Masculino , Idoso de 80 Anos ou mais , Feminino , Encéfalo/patologia , Encéfalo/metabolismo , Reserva Cognitiva/fisiologia , Peptídeos beta-Amiloides/metabolismo , Emaranhados Neurofibrilares/patologia , Emaranhados Neurofibrilares/metabolismo
14.
Eur J Neurol ; : e16465, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39240038

RESUMO

BACKGROUND AND PURPOSE: The purpose was to describe the risk of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, hospitalization for coronavirus disease 2019 (COVID-19) and related death and to assess the impact of the pandemic in the survival of amyotrophic lateral sclerosis (ALS) patients. METHODS: The risk of SARS-CoV-2 infection, hospitalization for COVID-19 and related death was assessed in ALS patients alive between March 2020 and July 2022. To evaluate its impact in the overall survival of ALS patients, the survival of patients who died before and during the pandemic was compared. RESULTS: Amongst 263 ALS patients alive during the pandemic, 62 got infected during the study period (infection rate 14.34 per 100 person-years). Most infections (68%) occurred during the sixth wave (November 2021 to January 2022) and most patients (67%) were vaccinated at the time of infection. The hospitalization rate due to COVID-19 was 4.16 per 100 person-years. The multivariable model confirmed non-invasive ventilation (NIV) use prior to infection as a risk factor for hospitalization (odds ratio [OR] = 7.96, p = 0.003) and COVID-19 vaccination as a protective factor (OR = 0.093, p = 0.025) independent of age, sex and gastrostomy. Within 30 days after infection, 7% of non-ventilated patients started NIV and five patients (8.06%) died, of whom four were previously ventilated. The median survival of ALS patients was similar before and during the pandemic and no effect was found in the Cox regression model (hazard ratio 1.02, p = 0.89). CONCLUSIONS: This study shows a high risk of severe COVID-19 amongst ALS patients requiring NIV. Nevertheless, the pandemic showed no impact in the overall survival of ALS patients, probably due to a high vaccination rate and an adequate access to healthcare resources.

15.
J Phys Chem A ; 128(26): 5158-5165, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38904331

RESUMO

The kinetic energy (KE) density plays an essential role in the stabilization mechanism of covalent, polar covalent, and ionic bondings; however, its role in metal-ligand bindings remains unclear. In a recent work, the energetic contributions of the spin densities α and ß were studied to explain the geometrical characteristics of a series of metal-ligand complexes. Notably, the KE density was found to modulate/stabilize the spin components of the intra-atomic nucleus-electron interactions within the metal in the complex. Here, we investigate the topographic properties of the spin components of the KE density for a family of high-spin hexa-aquo complexes ([M(H2O)6]2+) to shed light on the stabilization of the metal-ligand interaction. We compute the Lagrangian, G(r), and Hamiltonian, K(r), KE densities and analyze the evolution of its spin components in the formation of two metal-ligand coordination complexes. We study Kα/ß(r) along the metal-oxygen (M-O) internuclear axis as a function of the metal. Our results indicate that K(r) is a more distance-sensitive quantity compared to G(r) as it displays topographic features at larger M-O distances. Furthermore, K(r) allows one to identify the predominant interaction mechanism in the complexes.

16.
Eur J Appl Physiol ; 2024 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-39438314

RESUMO

Caffeine and beta-alanine are widely used in multi-ingredient pre-workout supplements believed to enhance resistance training, but their specific role in driving this effect remains unclear. The current study employed a randomized, triple-blinded, placebo-controlled and crossover experimental design to explore the acute effects of caffeine (200 mg), beta-alanine (3 g), or their combination (200 mg caffeine and 3 g beta-alanine; C+B-A) administered 30 min prior to resistance training (RT) on mechanical, physiological, and perceptual variables. Twenty-one young resistance-trained males (age = 23.5 ± 4.5 years, body mass = 82.1 ± 10.2 kg) visited the laboratory on six occasions: one familiarization session, one preliminary testing session for load determination, and four experimental sessions which differed only in supplementation condition and involved four supersets of bench press and bench pull exercises. The supplement condition did not significantly affect any mechanical variables (p ≥ 0.335), except for the velocity of the last repetition of the set, where beta-alanine produced lower values (0.383 m/s) compared to placebo (0.407 m/s; p < 0.05), with no differences observed for C+B-A (0.397 m/s) and caffeine (0.392 m/s). Heart rate was consistent across the different supplement conditions with the exception of the higher values observed immediately before the start of the RT session for placebo compared to caffeine (p = 0.010) and C+B-A (p = 0.019). Post-RT blood lactate concentration (p = 0.384), general and local ratings of perceived exertion (p = 0.177 and 0.160, respectively), and readiness (p = 0.281-0.925), did not differ significantly between supplement conditions. Selected supplements have minimal effects on performance and physiological responses in agonist-antagonist upper-body superset RT not leading to failure.

17.
Int J Sport Nutr Exerc Metab ; 34(5): 298-306, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38917985

RESUMO

The main objective of this placebo-controlled, triple-blind, balanced crossover study was to assess the acute effects of phenylcapsaicin (PC) intake (2.5 mg) on intraocular pressure (IOP), ocular perfusion pressure (OPP), and heart rate (HR) during a 30-min cycling task performed at 15% of the individual maximal power. Twenty-two healthy young adults performed the cycling task 45 min after ingesting PC or placebo. IOP was measured with a rebound tonometer before exercise, during cycling (every 6 min), and after 5 and 10 min of recovery. OPP was assessed before and after exercise. HR was monitored throughout the cycling task. We found an acute increase of IOP levels related to PC consumption while cycling (mean difference = 1.91 ± 2.24 mmHg; p = .007, ηp2=.30), whereas no differences were observed for OPP levels between the PC and placebo conditions (mean difference = 1.33 ± 8.70 mmHg; p = .608). Mean HR values were higher after PC in comparison with placebo intake (mean difference = 3.11 ± 15.87 bpm, p = .019, ηp2=.24), whereas maximum HR did not differ between both experimental conditions (p = .199). These findings suggest that PC intake before exercise should be avoided when reducing IOP levels is desired (e.g., glaucoma patients or those at risk). Future studies should determine the effects of different ergogenic aids on IOP and OPP levels with other exercise configurations and in the long term.


Assuntos
Ciclismo , Estudos Cross-Over , Frequência Cardíaca , Pressão Intraocular , Humanos , Pressão Intraocular/efeitos dos fármacos , Masculino , Adulto Jovem , Frequência Cardíaca/efeitos dos fármacos , Feminino , Adulto , Ciclismo/fisiologia
18.
Int J Mol Sci ; 25(19)2024 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-39409052

RESUMO

The objective of this study is to analyze the miRNA expression of oral fluids such as gingival crevicular fluid (GCF) in patients with periodontitis and Type 2 diabetes mellitus, and how these epigenetic biomarkers can influence the bidirectional relationship of these two inflammatory diseases. This review was conducted following the PRISMA criteria. PubMed, Scopus, Cochrane Library, Embase, and Web of Science databases were searched for clinical studies conducted on humans investigating, through GCF miRNA expression, the relationship between periodontal diseases and type 2 diabetes mellitus. In addition, the etiopathogenic pathways of the studied miRNAs were analyzed using the DIANA MIR path tool. A total of 1436 references were identified in the initial literature search, and seven articles were finally included in this review. Most of the articles included in this review were case-control studies and examined the expression of miRNAs in patients with periodontitis with or without diabetes. Due to their characteristics, miRNAs appear to be the ideal biomarkers for improving the understanding and knowledge of the etiopathogenic pathways that link both diseases. Among all the studied miRNAs, miR-146a, miR-155, miR-200b, miR-223, and miR-203 showed strong involvement in inflammatory and metabolic pathways, making them potential good diagnostic and prognostic biomarkers.


Assuntos
Biomarcadores , Diabetes Mellitus Tipo 2 , Epigênese Genética , MicroRNAs , Periodontite , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/complicações , Periodontite/genética , Periodontite/metabolismo , Biomarcadores/metabolismo , Líquido do Sulco Gengival/metabolismo
19.
J Strength Cond Res ; 38(5): 951-956, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38662887

RESUMO

ABSTRACT: González-Cano, H, Martín-Olmedo, JJ, Baz-Valle, E, Contreras, C, Schoenfeld, BJ, García-Ramos, A, Jiménez-Martínez, P, and Alix-Fages, C. Do muscle mass and body fat differ between elite and amateur natural physique athletes on competition day? A preliminary, cross-sectional, anthropometric study. J Strength Cond Res 38(5): 951-956, 2024-Natural physique athletes strive to achieve low body fat levels while promoting muscle mass hypertrophy for competition day. This study aimed to compare the anthropometric characteristics of natural amateur (AMA) and professional (PRO) World Natural Bodybuilding Federation (WNBF) competitors. Eleven male natural physique athletes (6 PRO and 5 AMA; age = 24.8 ± 2.3 years) underwent a comprehensive anthropometric evaluation following the International Society for the Advancement of Kinanthropometry protocol within a 24-hour time frame surrounding the competition. The 5-component fractionation method was used to obtain the body composition profile of the muscle, adipose, bone, skin, and residual tissues. Five physique athletes exceeded the 5.2 cutoff point of muscle-to-bone ratio (MBR) for natural athletes. Professional physique athletes were older than AMA physique athletes (p = 0.05), and they also presented larger thigh girths (p = 0.005) and bone mass (p = 0.019) compared with AMA physique athletes. Although no statistically significant between-group differences were observed in body mass, height, or body fat levels, PRO physique athletes exhibited a higher body mass index (BMI; AMA: 24.45 ± 0.12; PRO: 25.52 ± 1.01; p = 0.048), lean body mass (LBM; AMA: 64.49 ± 2.35; PRO: 69.80 ± 3.78; p = 0.024), fat-free mass (FFM; AMA: 71.23 ± 3.21; PRO: 76.52 ± 4.31; p = 0.05), LBM index (LBMI; AMA: 20.65 ± 0.52; PRO: 21.74 ± 0.85; p = 0.034), and fat-free mass index index (FFMI; AMA: 22.80 ± 0.22; PRO: 23.83 ± 0.90; p = 0.037) compared with AMA physique athletes. These findings highlight the unique characteristics and anthropometric differences between PRO and AMA natural physique athletes on competition day, emphasizing the significance of age, thigh girth, bone mass, BMI, LBM, FFM, and FFMI in distinguishing these 2 groups. Based on our findings, the established boundaries for muscle mass in natural physique athletes, based on FFMI and MBR, warrant reconsideration.


Assuntos
Tecido Adiposo , Antropometria , Atletas , Composição Corporal , Músculo Esquelético , Humanos , Masculino , Estudos Transversais , Adulto Jovem , Tecido Adiposo/anatomia & histologia , Tecido Adiposo/fisiologia , Músculo Esquelético/fisiologia , Músculo Esquelético/anatomia & histologia , Adulto , Composição Corporal/fisiologia , Levantamento de Peso/fisiologia
20.
Rev Med Chil ; 152(4): 476-482, 2024 Apr.
Artigo em Espanhol | MEDLINE | ID: mdl-39450816

RESUMO

Eighty percent of depressed patients in Primary Health Care (PHC) have a comorbidity. It is essential to contribute local evidence on the characteristics of patients with physical and psychiatric comorbidities to better address clinical practice. AIM: To characterize depressed patients from the cardiovascular program (PCV) of eight family health centers (CESFAM) in two communes of the Metropolitan Region. MATERIAL AND METHODS: Secondary analysis of data from a cluster-randomized clinical trial recruiting 359 program enrollees aged 18 years or older with a Patient Health Questionnaire 9-item (PHQ-9) score greater than or equal to 15. The inclusion criteria for participants were to be 18 years of age or older, to have a score on the Patient Health Questionnaire 9-item (PHQ-9) greater than or equal to 15, and to be enrolled in the cardiovascular program of the respective health center. RESULTS: These are mainly women users of the cardiovascular program with depressive symptoms of moderate to severe intensity with a previous depressive history (60.39%), previously treated in a (75.69%). Only 17.7% were using antidepressant drugs at the time of the interview.97.1% of the interviewees were using drugs for hypertension and/or diabetes. CONCLUSIONS: These are people with depressive episode, hypertension and/or diabetes who, having a personal and family history of depression, are not receiving pharmacological treatment for depression, which probably affects their quality of life. Better adherence to clinical guidelines for the treatment of depression is required.


Assuntos
Hipertensão , Atenção Primária à Saúde , Humanos , Feminino , Masculino , Atenção Primária à Saúde/estatística & dados numéricos , Hipertensão/epidemiologia , Hipertensão/tratamento farmacológico , Chile/epidemiologia , Pessoa de Meia-Idade , Adulto , Diabetes Mellitus/epidemiologia , Depressão/epidemiologia , Idoso , Comorbidade , Antidepressivos/uso terapêutico , Fatores Socioeconômicos
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