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1.
Neural Netw ; 179: 106486, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38986185

RESUMO

Reservoir computing approximation and generalization bounds are proved for a new concept class of input/output systems that extends the so-called generalized Barron functionals to a dynamic context. This new class is characterized by the readouts with a certain integral representation built on infinite-dimensional state-space systems. It is shown that this class is very rich and possesses useful features and universal approximation properties. The reservoir architectures used for the approximation and estimation of elements in the new class are randomly generated echo state networks with either linear or ReLU activation functions. Their readouts are built using randomly generated neural networks in which only the output layer is trained (extreme learning machines or random feature neural networks). The results in the paper yield a recurrent neural network-based learning algorithm with provable convergence guarantees that do not suffer from the curse of dimensionality when learning input/output systems in the class of generalized Barron functionals and measuring the error in a mean-squared sense.

3.
Hemasphere ; 8(7): e86, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38948924

RESUMO

Bridging therapy (BT) after leukapheresis is required in most relapsed/refractory (R/R) large B-cell lymphoma (LBCL) patients receiving chimeric antigen receptor (CAR) T cells. Bendamustine-containing regimens are a potential BT option. We aimed to assess if this agent had a negative impact on CAR-T outcomes when it was administered as BT. We included R/R LBCL patients from six centers who received systemic BT after leukapheresis from February 2019 to September 2022; patients who only received steroids or had pre-apheresis bendamustine exposure were excluded. Patients were divided into two BT groups, with and without bendamustine. Separate safety and efficacy analyses were carried out for axi-cel and tisa-cel. Of 243 patients who received BT, bendamustine (benda) was included in 62 (26%). There was a higher rate of BT progressors in the non-benda group (62% vs. 45%, p = 0.02). Concerning CAR-T efficacy, complete responses were comparable for benda versus non-benda BT cohorts with axi-cel (70% vs. 53%, p = 0.12) and tisa-cel (44% vs. 36%, p = 0.70). Also, 12-month progression-free and overall survival were not significantly different between BT groups with axi-cel (56% vs. 43% and 71% vs. 63%) and tisa-cel (25% vs. 26% and 52% vs. 48%); there were no differences when BT response was considered. CAR T-cell expansion for each construct was similar between BT groups. Regarding safety, CRS G ≥3 (6% vs. 6%, p = 0.79), ICANS G ≥3 (15% vs. 17%, p = 0.68), severe infections, and neutropenia post-infusion were comparable among BT regimens. BT with bendamustine-containing regimens is safe for patients requiring disease control during CAR T-cell manufacturing.

4.
Nat Med ; 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38830991

RESUMO

An unmet need exists for patients with relapsed/refractory (R/R) follicular lymphoma (FL) and high-risk disease features, such as progression of disease within 24 months (POD24) from first-line immunochemotherapy or disease refractory to both CD20-targeting agent and alkylator (double refractory), due to no established standard of care and poor outcomes. Chimeric antigen receptor (CAR) T cell therapy is an option in R/R FL after two or more lines of prior systemic therapy, but there is no consensus on its optimal timing in the disease course of FL, and there are no data in second-line (2L) treatment of patients with high-risk features. Lisocabtagene maraleucel (liso-cel) is an autologous, CD19-directed, 4-1BB CAR T cell product. The phase 2 TRANSCEND FL study evaluated liso-cel in patients with R/R FL, including 2L patients who all had POD24 from diagnosis after treatment with anti-CD20 antibody and alkylator ≤6 months of FL diagnosis and/or met modified Groupe d'Etude des Lymphomes Folliculaires criteria. Primary/key secondary endpoints were independent review committee-assessed overall response rate (ORR)/complete response (CR) rate. At data cutoff, 130 patients had received liso-cel (median follow-up, 18.9 months). Primary/key secondary endpoints were met. In third-line or later FL (n = 101), ORR was 97% (95% confidence interval (CI): 91.6‒99.4), and CR rate was 94% (95% CI: 87.5‒97.8). In 2L FL (n = 23), ORR was 96% (95% CI: 78.1‒99.9); all responders achieved CR. Cytokine release syndrome occurred in 58% of patients (grade ≥3, 1%); neurological events occurred in 15% of patients (grade ≥3, 2%). Liso-cel demonstrated efficacy and safety in patients with R/R FL, including high-risk 2L FL. ClinicalTrials.gov identifier: NCT04245839 .

5.
Genes (Basel) ; 15(4)2024 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-38674364

RESUMO

Satellite DNA (satDNA) consists of sequences of DNA that form tandem repetitions across the genome, and it is notorious for its diversity and fast evolutionary rate. Despite its importance, satDNA has been only sporadically studied in reptile lineages. Here, we sequenced genomic DNA and PCR-amplified microdissected W chromosomes on the Illumina platform in order to characterize the monomers of satDNA from the Henkel's leaf-tailed gecko U. henkeli and to compare their topology by in situ hybridization in the karyotypes of the closely related Günther's flat-tail gecko U. guentheri and gold dust day gecko P. laticauda. We identified seventeen different satDNAs; twelve of them seem to accumulate in centromeres, telomeres and/or the W chromosome. Notably, centromeric and telomeric regions seem to share similar types of satDNAs, and we found two that seem to accumulate at both edges of all chromosomes in all three species. We speculate that the long-term stability of all-acrocentric karyotypes in geckos might be explained from the presence of specific satDNAs at the centromeric regions that are strong meiotic drivers, a hypothesis that should be further tested.


Assuntos
Centrômero , Análise Citogenética , DNA Satélite , Cariótipo , Lagartos , Telômero , Animais , Lagartos/genética , Centrômero/genética , DNA Satélite/genética , Telômero/genética , Análise Citogenética/métodos , Hibridização in Situ Fluorescente
6.
Am J Physiol Endocrinol Metab ; 326(5): E648-E662, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38568152

RESUMO

We investigated if a bout of exercise in a hot environment (HEAT) would reduce the postprandial hyperglycemia induced by glucose ingestion. The hypothesis was that HEAT stimulating carbohydrate oxidation and glycogen use would increase the disposal of an ingested glucose load [i.e., oral glucose tolerance test (OGTT); 75 g of glucose]. Separated by at least 1 wk, nine young healthy individuals underwent three trials after an overnight fast in a randomized order. Two trials included 50 min of pedaling at 58 ± 5% V̇o2max either in a thermoneutral (21 ± 1°C; NEUTRAL) or in a hot environment (33 ± 1°C; HEAT) eliciting similar energy expenditure (503 ± 101 kcal). These two trials were compared with a no-exercise trial (NO EXER). Twenty minutes after exercise (or rest), subjects underwent an OGTT, while carbohydrate oxidation (CHOxid, using indirect calorimetry) plasma blood glucose, insulin concentrations (i.e., [glucose], [insulin]), and double tracer glucose kinetics ([U-13C] glucose ingestion and [6,6-2H2] glucose infusion) were monitored for 120 min. At rest, [glucose], [insulin], and rates of appearance/disappearance of glucose in plasma (glucose Ra/Rd) were similar among trials. During exercise, heart rate, tympanic temperature, [glucose], glycogen oxidation, and total CHOxid were higher during HEAT than NEUTRAL (i.e., 149 ± 35 vs. 124 ± 31 µmol·kg-1·min-1, P = 0.010). However, during the following OGTT, glucose Rd was similar in HEAT and NEUTRAL trials (i.e., 25.1 ± 3.6 vs. 25.2 ± 5.3 µmol·kg-1·min-1, P = 0.981). Insulin sensitivity (i.e., ISIndexMATSUDA) only improved in NEUTRAL compared with NO EXER (10.1 ± 4.6 vs. 8.8 ± 3.7 au; P = 0.044). In summary, stimulating carbohydrate use with exercise in a hot environment does not improve postprandial plasma glucose disposal or insulin sensitivity in a subsequent OGTT.NEW & NOTEWORTHY Exercise in the heat increases estimated muscle glycogen use. Reduced muscle glycogen after exercise in the heat could increase insulin-mediated glucose uptake during a subsequent oral glucose tolerance test (OGTT). However, plasma glucose kinetics are not improved during the OGTT in response to a bout of exercise in the heat, and insulin sensitivity worsens. Heat stress activates glucose counterregulatory hormones whose actions may linger during the OGTT, preventing increased glucose uptake.


Assuntos
Glicemia , Metabolismo dos Carboidratos , Metabolismo Energético , Exercício Físico , Teste de Tolerância a Glucose , Glucose , Temperatura Alta , Humanos , Masculino , Exercício Físico/fisiologia , Adulto , Adulto Jovem , Glicemia/metabolismo , Feminino , Metabolismo dos Carboidratos/fisiologia , Glucose/metabolismo , Metabolismo Energético/fisiologia , Insulina/sangue , Insulina/metabolismo , Oxirredução , Voluntários Saudáveis , Glicogênio/metabolismo , Período Pós-Prandial/fisiologia , Hiperglicemia/metabolismo , Hiperglicemia/prevenção & controle
7.
Adv Exp Med Biol ; 3234: 89-107, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38507202

RESUMO

Cellular machines formed by the interaction and assembly of macromolecules are essential in many processes of the living cell. These assemblies involve homo- and hetero-associations, including protein-protein, protein-DNA, protein-RNA, and protein-polysaccharide associations, most of which are reversible. This chapter describes the use of analytical ultracentrifugation, light scattering, and fluorescence-based methods, well-established biophysical techniques, to characterize interactions leading to the formation of macromolecular complexes and their modulation in response to specific or unspecific factors. We also illustrate, with several examples taken from studies on bacterial processes, the advantages of the combined use of subsets of these techniques as orthogonal analytical methods to analyze protein oligomerization and polymerization, interactions with ligands, hetero-associations involving membrane proteins, and protein-nucleic acid complexes.


Assuntos
Proteínas , RNA , Espectrometria de Fluorescência , Proteínas/química , Substâncias Macromoleculares , Ultracentrifugação/métodos
8.
PLoS One ; 19(2): e0294046, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38416741

RESUMO

The empirical laws governing human-curvilinear movements have been studied using various relationships, including minimum jerk, the 2/3 power law, and the piecewise power law. These laws quantify the speed-curvature relationships of human movements during curve tracing using critical speed and curvature as regressors. In this work, we provide a reservoir computing-based framework that can learn and reproduce human-like movements. Specifically, the geometric invariance of the observations, i.e., lateral distance from the closest point on the curve, instantaneous velocity, and curvature, when viewed from the moving frame of reference, are exploited to train the reservoir system. The artificially produced movements are evaluated using the power law to assess whether they are indistinguishable from their human counterparts. The generalisation capabilities of the trained reservoir to curves that have not been used during training are also shown.


Assuntos
Modelos Biológicos , Movimento , Humanos , Fenômenos Biomecânicos , Matemática , Generalização Psicológica
9.
Scand J Med Sci Sports ; 34(2): e14574, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38389141

RESUMO

AIM: To determine whether glucose volume of distribution (VdGLUCOSE ) affects the diagnosis of impaired insulin sensitivity (IS) when using an intravenous glucose tolerance test (IVGTT). METHODS: Individuals with distinct levels of IS underwent IVGTT after an overnight fast. The prediabetic group (Prediab; n = 33) differed from the healthy group (Healthy; n = 14) in their larger glycosylated hemoglobin (HbA1c of 5.9 ± 0.3 vs. 5.4 ± 0.1%; 41 ± 4 vs. 36 ± 1 mmol/mol; p < 0.001), percent body fat (37 ± 6 vs. 24 ± 3%; p < 0.001) and cardiovascular fitness level (VO2MAX 22 ± 5 vs. 44 ± 5 mL of O2 ·kg-1 ·min-1 ; p < 0.001). Ten minutes after intravenous infusion of the glucose bolus (i.e., 35 g in a 30% solution), VdGLUCOSE was assessed from the increases in plasma glucose concentration. IS was calculated during the next 50 min using the slope of glucose disappearance and the insulin time-response curve. RESULTS: VdGLUCOSE was higher in Healthy than in Prediab (230 ± 49 vs. 185 ± 21 mL·kg-1 ; p < 0.001). VdGLUCOSE was a strong predictor of IS (ß standardized coefficient 0.362; p = 0.004). VO2MAX was associated with VdGLUCOSE and IS (Pearson r = 0.582 and 0.704, respectively; p < 0.001). However, body fat was inversely associated with VdGLUCOSE and IS (r = -0.548 and -0.555, respectively; p < 0.001). CONCLUSIONS: Since fat mass is inversely related to VdGLUCOSE and in turn, VdGLUCOSE affects the calculations of IS, the IV glucose bolus dose should be calculated based on fat-free mass rather than body weight for a more accurate diagnosis of impaired IS.


Assuntos
Resistência à Insulina , Humanos , Teste de Tolerância a Glucose , Glucose , Insulina , Glicemia
10.
Nucleic Acids Res ; 52(4): 2045-2065, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38281216

RESUMO

The genome-organizing protein p6 of Bacillus subtilis bacteriophage φ29 plays an essential role in viral development by activating the initiation of DNA replication and participating in the early-to-late transcriptional switch. These activities require the formation of a nucleoprotein complex in which the DNA adopts a right-handed superhelix wrapping around a multimeric p6 scaffold, restraining positive supercoiling and compacting the viral genome. Due to the absence of homologous structures, prior attempts to unveil p6's structural architecture failed. Here, we employed AlphaFold2 to engineer rational p6 constructs yielding crystals for three-dimensional structure determination. Our findings reveal a novel fold adopted by p6 that sheds light on its self-association mechanism and its interaction with DNA. By means of protein-DNA docking and molecular dynamic simulations, we have generated a comprehensive structural model for the nucleoprotein complex that consistently aligns with its established biochemical and thermodynamic parameters. Besides, through analytical ultracentrifugation, we have confirmed the hydrodynamic properties of the nucleocomplex, further validating in solution our proposed model. Importantly, the disclosed structure not only provides a highly accurate explanation for previously experimental data accumulated over decades, but also enhances our holistic understanding of the structural and functional attributes of protein p6 during φ29 infection.


Assuntos
Fagos Bacilares , Bacillus subtilis , Fagos Bacilares/genética , Fagos Bacilares/química , Bacillus subtilis/virologia , Replicação do DNA , DNA Viral/genética , Nucleoproteínas/metabolismo , Proteínas Virais/metabolismo
11.
J Clin Oncol ; 42(2): 205-217, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-37874957

RESUMO

PURPOSE: Approximately 30%-40% of patients with relapsed/refractory (R/R) large B-cell lymphoma (LBCL) infused with CD19-targeted chimeric antigen receptor (CAR) T cells achieve durable responses. Consensus guidelines suggest avoiding bendamustine before apheresis, but specific data in this setting are lacking. We report distinct outcomes after CAR T-cell therapy according to previous bendamustine exposure. METHODS: The study included CAR T-cell recipients from seven European sites. Safety, efficacy, and CAR T-cell expansion kinetics were analyzed according to preapheresis bendamustine exposure. Additional studies on the impact of the washout period and bendamustine dose were performed. Inverse probability treatment weighting (IPTW) and propensity score matching (PSM) analyses were carried out for all efficacy comparisons between bendamustine-exposed and bendamustine-naïve patients. RESULTS: The study included 439 patients with R/R LBCL infused with CD19-targeted commercial CAR T cells, of whom 80 had received bendamustine before apheresis. Exposed patients had significantly lower CD3+ cells and platelets at apheresis. These patients had a lower overall response rate (ORR, 53% v 72%; P < .01), a shorter progression-free survival (PFS, 3.1 v 6.2 months; P = .04), and overall survival (OS, 10.3 v 23.5 months; P = .01) in comparison with the bendamustine-naïve group. Following adjustment methods for baseline variables, these differences were mitigated. Focusing on the impact of bendamustine washout before apheresis, those with recent (<9 months) exposure (N = 42) displayed a lower ORR (40% v 72%; P < .01), shorter PFS (1.3 v 6.2 months; P < .01), and OS (4.6 v 23.5 months; P < .01) in comparison with bendamustine-naïve patients. These differences remained significant after IPTW and PSM analysis. Conversely, the cumulative dose of bendamustine before apheresis did not affect CAR-T efficacy outcomes. CONCLUSION: Recent bendamustine exposure before apheresis was associated with negative treatment outcomes after CD19-targeted CAR T-cell therapy and should be therefore avoided in CAR T-cell candidates.


Assuntos
Remoção de Componentes Sanguíneos , Linfoma Difuso de Grandes Células B , Receptores de Antígenos Quiméricos , Humanos , Cloridrato de Bendamustina/efeitos adversos , Imunoterapia Adotiva/efeitos adversos , Antígenos CD19 , Terapia Baseada em Transplante de Células e Tecidos
12.
Arch Biochem Biophys ; 751: 109836, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38000493

RESUMO

Fungal ribotoxins are extracellular RNases that inactivate ribosomes by cleaving a single phosphodiester bond at the universally conserved sarcin-ricin loop of the large rRNA. However, to reach the ribosomes, they need to cross the plasma membrane. It is there where these toxins show their cellular specificity, being especially active against tumoral or virus-infected cells. Previous studies have shown that fungal ribotoxins interact with negatively charged membranes, typically containing phosphatidylserine or phosphatidylglycerol. This ability is rooted on their long, non-structured, positively charged loops, and its N-terminal ß-hairpin. However, its effect on complex lipid mixtures, including sphingophospholipids or cholesterol, remains poorly studied. Here, wild-type α-sarcin was used to evaluate its interaction with a variety of membranes not assayed before, which resemble much more closely mammalian cell membranes. The results confirm that α-sarcin is particularly sensitive to charge density on the vesicle surface. Its ability to induce vesicle aggregation is strongly influenced by both the lipid headgroup and the degree of saturation of the fatty acid chains. Acyl chain length is indeed particularly important for lipid mixing. Finally, cholesterol plays an important role in diluting the concentration of available negative charges and modulates the ability of α-sarcin to cross the membrane.


Assuntos
Endorribonucleases , Proteínas Fúngicas , Colesterol , Endorribonucleases/química , Proteínas Fúngicas/química , Lipídeos
13.
Sci Adv ; 9(45): eadf7997, 2023 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-37948524

RESUMO

Amyotrophic lateral sclerosis and frontotemporal dementia patients with a hexanucleotide repeat expansion in C9ORF72 (C9-HRE) accumulate poly-GR and poly-PR aggregates. The pathogenicity of these arginine-rich dipeptide repeats (R-DPRs) is thought to be driven by their propensity to bind low-complexity domains of multivalent proteins. However, the ability of R-DPRs to bind native RNA and the significance of this interaction remain unclear. Here, we used computational and experimental approaches to characterize the physicochemical properties of R-DPRs and their interaction with RNA. We find that poly-GR predominantly binds ribosomal RNA (rRNA) in cells and exhibits an interaction that is predicted to be energetically stronger than that for associated ribosomal proteins. Critically, modified rRNA "bait" oligonucleotides restore poly-GR-associated ribosomal deficits and ameliorate poly-GR toxicity in patient neurons and Drosophila models. Our work strengthens the hypothesis that ribosomal function is impaired by R-DPRs, highlights a role for direct rRNA binding in mediating ribosomal dysfunction, and presents a strategy for protecting against C9-HRE pathophysiological mechanisms.


Assuntos
Esclerose Lateral Amiotrófica , Demência Frontotemporal , Animais , Humanos , Demência Frontotemporal/genética , Esclerose Lateral Amiotrófica/genética , Proteína C9orf72/genética , Proteína C9orf72/metabolismo , RNA Ribossômico/genética , Sequenciamento de Cromatina por Imunoprecipitação , RNA/genética , Drosophila/genética , Drosophila/metabolismo , Expansão das Repetições de DNA
14.
J Physiol ; 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38015017

RESUMO

A supervised intense aerobic exercise program improves the health of individuals with metabolic syndrome (MetS). However, it is unclear whether the timing of training within the 24 h day would influence those health benefits. The present study aimed to determine the influence of morning vs. afternoon exercise on body composition, cardiometabolic health and components of MetS. One hundred thirty-nine individuals with MetS were block randomized into morning (AMEX; n = 42) or afternoon (PMEX; n = 59) exercise training groups, or a non-training control group (Control; n = 38). Exercise training was comprised of 48 supervised high-intensity interval sessions distributed over 16 weeks. Body composition, cardiorespiratory fitness (assessed by V ̇ O 2 max ${\dot V_{{{\mathrm{O}}_{\mathrm{2}}}{\mathrm{max}}}}$ ), maximal fat oxidation (FOmax ), blood pressure and blood metabolites were assessed before and after the intervention. Compared with the non-training Control, both exercise groups improved similarly body composition (-0.7% fat loss; P = 0.002), waist circumference (-2.1 cm; P < 0.001), diastolic blood pressure (-3.8 mmHg; P = 0.004) and V ̇ O 2 max ${\dot V_{{{\mathrm{O}}_{\mathrm{2}}}{\mathrm{max}}}}$ (3.5 mL kg-1   min-1 ; P < 0.001) with no differences between training groups. AMEX, in comparison with PMEX, reduced systolic blood pressure (-4% vs. -1%; P = 0.019), plasma fasting insulin concentration (-12% vs. -5%; P = 0.001) and insulin resistance (-14% vs. -4%; P = 0.006). Furthermore, MetS Z score was further reduced in the AMEX compared to PMEX (-52% vs. -19%; P = 0.021) after training. In summary, high-intensity aerobic exercise training in the morning in comparison to training in the afternoon is somewhat more efficient at reducing cardiometabolic risk factors (i.e. systolic blood pressure and insulin sensitivity). KEY POINTS: The effect of exercise time of day on health promotion is an area that has gained interest in recent years; however, large-scale, randomized-control studies are scarce. People with metabolic syndrome (MetS) are at risk of developing cardiometabolic diseases and reductions in this risk with exercise training can be precisely gauged using a compound score sensitive to subtle evolution in each MetS component (i.e. Z score). Supervised aerobic exercise for 16 weeks (morning and afternoon), without dietary restriction, improved cardiorespiratory and metabolic fitness, body composition and mean arterial pressure compared to a non-exercise control group. However, training in the morning, without changes in exercise dose or intensity, reduced systolic blood pressure and insulin resistance further compared to when training in the afternoon. Thus, high-intensity aerobic exercise training in the morning is somewhat more efficient in improving the health of individuals with metabolic syndrome.

15.
Int J Mol Sci ; 24(19)2023 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-37834228

RESUMO

The aim of this paper was to review the available evidence on the efficacy and safety of combined or sequential use of PD-1/PD-L1 immune checkpoint inhibitors (ICI) and CAR-T cell therapies in relapsed/refractory (R/R) haematological malignancies. A systematic literature review was performed until 21 November 2022. Inclusion criteria: cohort studies/clinical trials aimed at evaluating the efficacy and/or safety of the combination of CAR-T cell therapy with PD-1/PD-L1 inhibitors in R/R haematological malignancies, which had reported results. Those focusing only on ICI or CAR-T separately or evaluating the combination in other non-hematological solid tumours were excluded. We used a specific checklist for quality assessment of the studies, and then we extracted data on efficacy or efficiency and safety. A total of 1867 articles were identified, and 9 articles were finally included (early phase studies, with small samples of patients and acceptable quality). The main pathologies were B-cell acute lymphoblastic leukaemia (B-ALL) and B-cell non-Hodgkin's lymphoma (B-NHL). The most studied combination was tisagenlecleucel with pembrolizumab. In terms of efficacy, there is great variability: the combination could be a promising option in B-ALL, with modest data, and in B-NHL, although hopeful responses were received, the combination does not appear better than CAR-T cell monotherapy. The safety profile could be considered comparable to that described for CAR-T cell monotherapy.


Assuntos
Neoplasias Hematológicas , Receptores de Antígenos Quiméricos , Humanos , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Receptor de Morte Celular Programada 1 , Recidiva Local de Neoplasia , Neoplasias Hematológicas/terapia , Imunoterapia Adotiva/métodos , Linfócitos T
16.
Rep Pract Oncol Radiother ; 28(4): 529-540, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37795225

RESUMO

Background: The purpose was to validate the PRIMO Monte Carlo software to be used during the commissioning of a treatment planning system (TPS). Materials and methods: The Acuros XB v. 16.1 algorithm of the Eclipse was configured for 6 MV and 6 MV flattening-filter-free (FFF) photon beams, from a TrueBeam linac equipped with a high-definition 120-leaf multileaf collimator (MLC). PRIMO v. 0.3.64.1814 software was used with the phase space files provided by Varian and benchmarked against the reference dosimetry dataset published by the Imaging and Radiation Oncology Core-Houston (IROC-H). Thirty Eclipse clinical intensity-modulated radiation therapy (IMRT)/volumetric modulated arc therapy (VMAT) plans were verified in three ways: 1) using the PTW Octavius 4D (O4D) system; 2) the Varian Portal Dosimetry system and 3) the PRIMO software. Clinical validation of PRIMO was completed by comparing the simulated dose distributions on the O4D phantom against dose measurements for these 30 clinical plans. Agreement evaluations were performed using a 3% global/2 mm gamma index analysis. Results: PRIMO simulations agreed with the benchmark IROC-H data within 2.0% for both energies. Gamma passing rates (GPRs) from the 30 clinical plan verifications were (6 MV/6MV FFF): 99.4% ± 0.5%/99.9% ± 0.1%, 99.8% ± 0.4%/98.9% ± 1.4%, 99.7% ± 0.4%/99.7% ± 0.4%, for the 1), 2) and 3) verification methods, respectively. Agreement between PRIMO simulations on the O4D phantom and 3D dose measurements resulted in GPRs of 97.9% ± 2.4%/99.7% ± 0.4%. Conclusion: The PRIMO software is a valuable tool for dosimetric verification of clinical plans during the commissioning of the primary TPS.

17.
Am J Physiol Endocrinol Metab ; 325(4): E310-E324, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37584610

RESUMO

The potential interaction between metformin and exercise on glucose-lowering effects remains controversial. We studied the separated and combined effects of metformin and/or exercise on fasting and postprandial insulin sensitivity in individuals with pre-diabetes and type 2 diabetes (T2D). Eight T2D adults (60 ± 4 yr) with overweight/obesity (32 ± 4 kg·m-2) under chronic metformin treatment (9 ± 6 yr; 1281 ± 524 mg·day-1) underwent four trials; 1) taking their habitual metformin treatment (MET), 2) substituting during 96 h their metformin medication by placebo (PLAC), 3) placebo combined with 50 min bout of high-intensity interval exercise (PLAC + EX), and 4) metformin combined with exercise (MET + EX). Plasma glucose kinetics using stable isotopes (6,6-2H2 and [U-13C] glucose), and glucose oxidation by indirect calorimetry, were assessed at rest, during exercise, and in a subsequent oral glucose tolerance test (OGTT). Postprandial glucose and insulin concentrations were analyzed as mean and incremental area under the curve (iAUC), and insulin sensitivity was calculated (i.e., MATSUDAindex and OGISindex). During OGTT, metformin reduced glucose iAUC (i.e., MET and MET + EX lower than PLAC and PLAC + EX, respectively; P = 0.023). MET + EX increased MATSUDAindex above PLAC (4.8 ± 1.4 vs. 3.3 ± 1.0, respectively; P = 0.018) and OGISindex above PLAC (358 ± 52 vs. 306 ± 46 mL·min-1·m-2, respectively; P = 0.006). Metformin decreased the plasma appearance of the ingested glucose (Ra OGTT; MET vs. PLAC, -3.5; 95% CI -0.1 to -6.8 µmol·kg-1·min-1; P = 0.043). Metformin combined with exercise potentiates insulin sensitivity during an OGTT in individuals with pre-diabetes and type 2 diabetes. Metformin's blood glucose-lowering effect seems mediated by decreased oral glucose entering the circulation (gut-liver effect) an effect partially blunted after exercise.NEW & NOTEWORTHY Metformin is the most prescribed oral antidiabetic medicine in the world but its mechanism of action and its interactions with exercise are not fully understood. Our stable isotope tracer data suggested that metformin reduces the rates of oral glucose entering the circulation (gut-liver effect). Exercise, in turn, tended to reduce postprandial insulin blood levels potentiating metformin improvements in insulin sensitivity. Thus, exercise potentiates metformin improvements in glycemic control and should be advised to metformin users.


Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Metformina , Estado Pré-Diabético , Adulto , Humanos , Metformina/farmacologia , Metformina/uso terapêutico , Glucose , Estado Pré-Diabético/tratamento farmacológico , Cinética , Glicemia , Insulina
18.
J Clin Endocrinol Metab ; 109(1): 80-91, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-37565392

RESUMO

BACKGROUND: The risk for atherogenic plaque formation is high after ingestion of meals in individuals with high blood lipid levels (ie, dyslipidemia). Statins and exercise reduce the rise of blood triglyceride concentrations after a meal, but the effect of their combination is unclear. METHODS: In a randomized crossover design, 11 individuals with dyslipidemia and metabolic syndrome treated with statins underwent a mixed-meal (970 ± 111 kcal, 24% fat, and 34% carbohydrate) tolerance test. Plasma lipid concentrations, fat oxidation, glucose, and glycerol kinetics were monitored immediately prior and during the meal test. Trials were conducted with participants under their habitual statin treatment and 96 hours after blinded statin withdrawal. Trials were duplicated after a prolonged bout of low-intensity exercise (75 minutes at 53 ± 4% maximal oxygen consumption) to study the interactions between exercise and statins. RESULTS: Statins reduced postprandial plasma triglycerides from 3.03 ± 0.85 to 2.52 ± 0.86 mmol·L-1 (17%; P = .015) and plasma glycerol concentrations (ie, surrogate of whole-body lipolysis) without reducing plasma free fatty acid concentration or fat oxidation. Prior exercise increased postprandial plasma glycerol levels (P = .029) and fat oxidation rates (P = .024). Exercise decreased postprandial plasma insulin levels (241 ± 116 vs 301 ± 172 ρmol·L-1; P = .026) but not enough to increase insulin sensitivity (P = .614). Neither statins nor exercise affected plasma glucose appearance rates from exogenous or endogenous sources. CONCLUSIONS: In dyslipidemic individuals, statins reduce blood triglyceride concentrations after a meal, but without limiting fat oxidation. Statins do not interfere with exercise lowering the postprandial insulin that likely promotes fat oxidation. Last, statins do not restrict the rates of plasma incorporation or oxidation of the ingested glucose.


Assuntos
Dislipidemias , Inibidores de Hidroximetilglutaril-CoA Redutases , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Glicemia/metabolismo , Glicerol , Glucose , Triglicerídeos , Insulina , Lipídeos , Dislipidemias/tratamento farmacológico , Período Pós-Prandial
20.
Sensors (Basel) ; 23(13)2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-37447992

RESUMO

In order to ensure sufficient recovery of the human body and brain, healthy sleep is indispensable. For this purpose, appropriate therapy should be initiated at an early stage in the case of sleep disorders. For some sleep disorders (e.g., insomnia), a sleep diary is essential for diagnosis and therapy monitoring. However, subjective measurement with a sleep diary has several disadvantages, requiring regular action from the user and leading to decreased comfort and potential data loss. To automate sleep monitoring and increase user comfort, one could consider replacing a sleep diary with an automatic measurement, such as a smartwatch, which would not disturb sleep. To obtain accurate results on the evaluation of the possibility of such a replacement, a field study was conducted with a total of 166 overnight recordings, followed by an analysis of the results. In this evaluation, objective sleep measurement with a Samsung Galaxy Watch 4 was compared to a subjective approach with a sleep diary, which is a standard method in sleep medicine. The focus was on comparing four relevant sleep characteristics: falling asleep time, waking up time, total sleep time (TST), and sleep efficiency (SE). After evaluating the results, it was concluded that a smartwatch could replace subjective measurement to determine falling asleep and waking up time, considering some level of inaccuracy. In the case of SE, substitution was also proved to be possible. However, some individual recordings showed a higher discrepancy in results between the two approaches. For its part, the evaluation of the TST measurement currently does not allow us to recommend substituting the measurement method for this sleep parameter. The appropriateness of replacing sleep diary measurement with a smartwatch depends on the acceptable levels of discrepancy. We propose four levels of similarity of results, defining ranges of absolute differences between objective and subjective measurements. By considering the values in the provided table and knowing the required accuracy, it is possible to determine the suitability of substitution in each individual case. The introduction of a "similarity level" parameter increases the adaptability and reusability of study findings in individual practical cases.


Assuntos
Transtornos do Sono-Vigília , Sono , Humanos , Polissonografia/métodos , Estudos de Viabilidade , Inquéritos e Questionários
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