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2.
An Acad Bras Cienc ; 96(suppl 1): e20240297, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39319866

RESUMO

Data about the impacts of hemodialysis on antioxidant status and markers of oxidative stress are controversial, probably due to the use of different methodological approaches. The aim of this study was to assess the changes in the oxidative damage markers and antioxidant enzymes, and the serum antioxidant capacity by using in vitro model systems of free radical generation before and after one hemodialysis session. Blood samples were collected from 40 patients with kidney failure before and after hemodialysis. In pre- and post-hemodialysis serum samples, concentrations of biomarkers of oxidative damage and the activities of antioxidant enzymes were measured, as well as the in vitro antioxidant potential. The high concentrations of oxidative stress markers in serum of kidney failure patients were decreased after one hemodialysis session. In pre-hemodialysis, low activities of antioxidant enzymes were observed, including paraoxonase-1, however paraoxonase-1 activity was partially recovered after hemodialysis. Crocin bleaching and radical scavenging assays showed that serum antioxidant potential was decreased after hemodialysis. Although one hemodialysis session increased paraoxonase-1 activity and decreased oxidative stress markers, it caused a decrease in the serum antioxidant potential. Future research is needed to prospect strategies to mitigate the impacts of oxidative stress in the scenario of hemodialysis repetitions.


Assuntos
Antioxidantes , Biomarcadores , Estresse Oxidativo , Diálise Renal , Humanos , Estresse Oxidativo/fisiologia , Diálise Renal/efeitos adversos , Biomarcadores/sangue , Masculino , Antioxidantes/metabolismo , Antioxidantes/análise , Feminino , Pessoa de Meia-Idade , Arildialquilfosfatase/sangue , Adulto , Insuficiência Renal/sangue , Insuficiência Renal/terapia , Falência Renal Crônica/terapia , Falência Renal Crônica/sangue , Idoso
3.
Gastroenterology ; 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39214503

RESUMO

BACKGROUND & AIMS: The authors assessed whether familial colorectal cancer (FCRC) surveillance in individuals without hereditary CRC can be optimized METHODS: The Adenoma and Serrated Pathway to Colorectal Cancer-FCRC model simulates CRC development in individuals with a family history of CRC at 2-fold and 4-fold increased CRC risk compared with the general population. The authors simulated a strategy without surveillance, the current Dutch guideline (5-yearly colonoscopy between ages 45 and 75 years), and the following 3 sets of alternative strategies: colonoscopy surveillance, surveillance combining colonoscopy and fecal immunochemical test (FIT), and FIT-based surveillance. Each set included a range of strategies differing in age range and test interval. The optimal strategy was defined as the strategy with highest quality-adjusted life-years (QALYs) satisfying all of the following criteria: in the (near-)efficiency area of the cost-effectiveness frontier and compared with current surveillance; noninferior effectiveness; no substantial increase in colonoscopy burden; and not more expensive. RESULTS: The optimal strategy was 10-yearly colonoscopy with 2-yearly FIT between colonoscopies from ages 40 to 80 years for both 2-fold and 4-fold increased CRC risk. At 2-fold risk, this strategy prevented 0.8 more CRC deaths, gained 15.8 more QALYs at 731 fewer colonoscopies, and saved €98,000 over the lifetime of 1000 individuals compared with current surveillance. At 4-fold risk, figures were 2.1 more CRC deaths prevented, 37.0 more QALYs gained at 567 fewer colonoscopies, and €127,000 lower costs. Current surveillance was not (near-)efficient. CONCLUSIONS: FIT could play an important role in FCRC surveillance. Surveillance with 10-yearly colonoscopy and 2-yearly FIT between colonoscopies from ages 40 to 80 years increased QALYs and reduced colonoscopy burden and costs compared with current FCRC surveillance.

4.
Pancreatology ; 24(6): 847-855, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39155165

RESUMO

BACKGROUND: Acute pancreatitis is a common disease that is usually mild and self-limiting. Early discharge of patients with mild acute pancreatitis, with the use of supporting outpatient services including remote monitoring or smartphone applications, might be safe and could reduce the healthcare demand. The objective of this review was to provide a comprehensive overview of existing strategies aimed at facilitating early discharge of patients diagnosed with mild acute pancreatitis and to assess clinical outcomes, feasibility and costs associated with these strategies. METHODS: PubMed, Cochrane, Embase, and Web of Science were systematically searched, to identify studies that evaluated strategies to reduce the length of hospital stay in patients with mild acute pancreatitis. RESULTS: Five studies, including 84 to 419 patients each, were identified and described three different early discharge protocols. The early discharge strategies resulted in a median length of hospital stay of a minimum of 6 to a maximum of 23 h in these studies. Early discharge compared to usual care did not result in increased 30-day readmissions. Additionally, no occurrences of complications or mortality were observed in either group. A significant reduction in overall costs was reported ranging from 43.1 % to 85.4 %. CONCLUSIONS: Early discharge of patients with mild acute pancreatitis seems both feasible and safe. Further studies are warranted, since focus on safe early discharge could significantly reduce inpatient healthcare utilization and associated costs.


Assuntos
Tempo de Internação , Pancreatite , Alta do Paciente , Humanos , Pancreatite/terapia , Doença Aguda
5.
Sci Rep ; 14(1): 15015, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38951589

RESUMO

Predicting physical properties of complex multi-scale systems is a common challenge and demands analysis of various temporal and spatial scales. However, physics alone is often not sufficient due to lack of knowledge on certain details of the system. With sufficient data, however, machine learning techniques may aid. If data are yet relatively cumbersome to obtain, hybrid methods may come to the rescue. We focus in this report on using various types of neural networks (NN) including NN's into which physics information is encoded (PeNN's) and also studied effects of NN's hyperparameters. We apply the networks to predict the viscosity of an emulsion as a function of shear rate. We show that using various network performance metrics as the mean squared error and the coefficient of determination ( R 2 ) that the PeNN's always perform better than the NN's, as also confirmed by a Friedman test with a p-value smaller than 0.0002. The PeNN's capture extrapolation and interpolation very well, contrary to the NN's. In addition, we have found that the NN's hyperparameters including network complexity and optimization methods do not have any effect on the above conclusions. We suggest that encoding NN's with any disciplinary system based information yields promise to better predict properties of complex systems than NN's alone, which will be in particular advantageous for small numbers of data. Such encoding would also be scalable, allowing different properties to be combined, without repetitive training of the NN's.

6.
Gait Posture ; 113: 330-336, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39024986

RESUMO

BACKGROUND: Voluntary stepping tasks are used to measure the ability of an individual to step and has been associated with fall risk in older adults. Although electromyography (EMG) amplitude is measured during stepping tasks, there is no consensus about the reference EMG value that should be used to normalize the signal. The purpose of the present study was to 1) investigate the impact of using different EMG parameters as a reference to normalize the rate of activation (RoA) of the hip abductor muscles across lateral voluntary step trials and the differences between trials, and 2) to investigate the reliability among trials of the reference EMG values. METHODS: Nineteen older adults (>65 years of age) performed ten lateral choice reaction stepping test (CRST), while the gluteus medius and tensor fascia latae EMG were recorded. Three reference EMG values were calculated and used to normalize RoA during the stepping task. A repeated-measures ANOVA was used (normalized RoA[3] x trial[3]) to compare normalized EMG across trials, and an intraclass correlation coefficient and coefficient of variation were used for the inter-trial reliability of the reference EMG values. RESULTS: The present study showed that gluteus medius and tensor fascia latae RoA normalized values from the stance and stepping leg (right or left side) measured during CRST are different according to the reference EMG value(P<0.001), with no differences across trials. Overall, the EMG procedures showed high inter-trial reliability, with a few exceptions. SIGNIFICANCE: Therefore, after careful examination of our results, the peak and mean EMG amplitudes showed consistently higher intraclass correlation coefficients; however, the former may provide a more intuitive reference value.


Assuntos
Eletromiografia , Músculo Esquelético , Humanos , Idoso , Feminino , Masculino , Músculo Esquelético/fisiologia , Reprodutibilidade dos Testes , Articulação do Quadril/fisiologia , Idoso de 80 Anos ou mais , Valores de Referência
7.
J Transl Med ; 22(1): 621, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38961395

RESUMO

BACKGROUND: The tumor microenvironment is profoundly heterogeneous particularly when comparing sites of metastases. Establishing the extent of this heterogeneity may provide guidance on how best to design lipid-based drug delivery systems to treat metastatic disease. Building on our previous research, the current study employs a murine model of metastatic cancer to explore the distribution of ~ 100 nm liposomes. METHODS: Female NCr nude mice were inoculated with a fluorescently labeled, Her2/neu-positive, trastuzumab-resistant breast cancer cell line, JIMT-1mkate, either in the mammary fat pad to create an orthotopic tumor (OT), or via intracardiac injection (IC) to establish tumors throughout the body. Animals were dosed with fluorescent and radio-labeled liposomes. In vivo and ex vivo fluorescent imaging was used to track liposome distribution over a period of 48 h. Liposome distribution in orthotopic tumors was compared to sites of tumor growth that arose following IC injection. RESULTS: A significant amount of inter-vessel heterogeneity for DiR distribution was observed, with most tumor blood vessels showing little to no presence of the DiR-labelled liposomes. Further, there was limited extravascular distribution of DiR liposomes in the perivascular regions around DiR-positive vessels. While all OT tumors contained at least some DiR-positive vessels, many metastases had very little or none. Despite the apparent limited distribution of liposomes within metastases, two liposomal drug formulations, Irinophore C and Doxil, showed similar efficacy for both the OT and IC JIMT-1mkate models. CONCLUSION: These findings suggest that liposomal formulations achieve therapeutic benefits through mechanisms that extend beyond the enhanced permeability and retention effect.


Assuntos
Antineoplásicos , Lipossomos , Camundongos Nus , Metástase Neoplásica , Animais , Linhagem Celular Tumoral , Feminino , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Antineoplásicos/farmacocinética , Antineoplásicos/administração & dosagem , Humanos , Resultado do Tratamento , Camundongos
8.
J Ultrasound ; 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39060718

RESUMO

PURPOSE: The aim was to compare the use of different tools within the ImageJ program (polygon vs. segmented line) and their impact on the calculation of muscle area and echo intensity (EI) values in ultrasound imaging of the vastus lateralis muscle. METHODS: Thirteen volunteers participated in this study. Ultrasound images of the vastus lateralis muscle were acquired using 2D B-mode ultrasonography and analyzed using both the polygon and segmented line tools by the same evaluator. The intraclass correlation coefficient (ICC) and coefficient of variation (CV) assessed the tools' reliability. Bland-Altman plots were employed to verify the agreement between measurements, and linear regression analysis determined proportional bias. A paired t-test was conducted to analyze differences between the tools. RESULTS: The reliability between tools for muscle area calculation was weak (r = 0.000; CV = 138.03 ± 0.34%), while it was excellent for EI (r = 0.871; CV = 15.19 ± 2.96%). The Bland-Altman plots indicated a large bias for muscle area (d = 195.2%) with a proportional bias (p < 0.001). For EI, the bias was (d = 15.2) with proportional bias (p = 0.028). The paired t-test revealed significant differences between the tools for area (p < 0.001) but not for EI (p = 0.060). CONCLUSION: The study found significant differences in measurements obtained with the polygon and segmented line tools in ImageJ, with the polygon tool showing higher values for muscle area and lower values for EI.

9.
Front Immunol ; 15: 1354617, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38638438

RESUMO

Introduction: Innate lymphoid cells (ILCs) have been implicated in multiple pathologic conditions, including atherogenesis, as documented in experimental mice studies, however, their role in atherosclerosis in humans remains unexplored. Methods: Here, we identify ILCs and their dynamics in early, advanced, and complicated human carotid- and aortic atherosclerotic plaques, using a multiplex immunohistochemical quadruple-staining technique with prototypic transcription factors T-bet, GATA3, or RORgt for identification of the ILC1, ILC2 and ILC3 subsets, respectively, in combination with lineage markers CD3, CD20/ CD79a and CD56 to exclude other lymphoid cell types. ILC subsets were quantified, and to put this in perspective, their numbers were expressed as percentage of the total number of infiltrated lymphoid cells and related to the frequency of conventional T cells, B cells, NK cells, and NKT cells. Results: All ILC subsets were present in every different stage of atherogenesis. ILC1s were the most abundant ILC subset, and their numbers significantly increased in the course of plaque development, but paradoxically, their relative frequency was reduced because of a higher increment of T cells and B cells. The numbers of ILC2s and ILC3s also gradually increased, but this trend did not achieve significance. T cell subsets always significantly outnumbered their ILC counterparts, except for the early lesions where the proportion of ILC1s was markedly higher, albeit not significant. Discussion: The high abundance of ILC1s in the early stages and further significant enrichment in later stages, suggest they may participate in the initiation and development of atherogenesis, and thus, may represent a novel target to prevent or treat atherosclerosis.


Assuntos
Aterosclerose , Placa Aterosclerótica , Humanos , Camundongos , Animais , Imunidade Inata , Células Matadoras Naturais
10.
J Appl Physiol (1985) ; 136(6): 1568-1579, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38660724

RESUMO

There is a marked difference between males and females in sprint running performance, yet a comprehensive investigation of sex differences in the muscle morphology of sprinters, which could explain the performance differences, remains to be completed. This study compared muscle volumes of 23 individual leg muscles and 5 functional muscle groups, assessed with 3 T magnetic resonance imaging, between male (n = 31) and female (n = 22) sprinters, as well as subgroups of elite males (EM, n = 5), elite females (EF, n = 5), and performance-matched (to elite females) males (PMMEF, n = 6). Differences in muscle volume distribution between EM, EF, and unathletic male (UM) controls were also assessed. For the full cohorts, male sprinters were more muscular than their female counterparts, but the differences were nonuniform and anatomically variable, with the largest differences in the hip extensors and flexors. However, among elite sprinters the sex differences in the volume of the functional muscle groups were almost uniform (absolute volume +47-53%), and the muscle volume distribution of EM was more similar to EF than to UM (P < 0.039). For PMMEF, relative hip extensor volume, but not stature or percent body fat, differentiated for performance (PMMEF and EF < EM) rather than sex. In conclusion, although the full cohorts of sprinters showed a marked sex difference in the amount and distribution of muscle mass, elite sprinters appeared to be selected for a common muscle distribution phenotype that for these elite subgroups was a stronger effect than that of sex. Relative hip extensor muscle volume, rather than stature, percent body fat, or total relative muscle volume, appeared to be the primary determinant of the sex difference in performance.NEW & NOTEWORTHY We present novel evidence suggesting muscle volume, specifically relative hip extensor volume, may be a primary deterministic variable for the sex difference in sprint performance, such that with matched sprint times, male and female sprinters may be expected to have equivalent muscle morphology. We highlight striking similarities in distribution of leg muscle mass between elite male and female sprinters and provide evidence for the existence of a muscular distribution phenotype specific to elite sprinters, irrespective of sex.


Assuntos
Músculo Esquelético , Corrida , Caracteres Sexuais , Humanos , Masculino , Feminino , Músculo Esquelético/fisiologia , Músculo Esquelético/anatomia & histologia , Músculo Esquelético/diagnóstico por imagem , Corrida/fisiologia , Adulto Jovem , Adulto , Imageamento por Ressonância Magnética/métodos , Atletas , Desempenho Atlético/fisiologia , Perna (Membro)/fisiologia , Perna (Membro)/anatomia & histologia , Fatores Sexuais
11.
Endoscopy ; 56(7): 484-493, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38325403

RESUMO

BACKGROUND: The incidence of T1 colorectal cancer (CRC) has increased with the implementation of CRC screening programs. It is unknown whether the outcomes and risk models for T1 CRC based on non-screen-detected patients can be extrapolated to screen-detected T1 CRC. This study aimed to compare the stage distribution and oncologic outcomes of T1 CRC patients within and outside the screening program. METHODS: Data from T1 CRC patients diagnosed between 2014 and 2017 were collected from 12 hospitals in the Netherlands. The presence of lymph node metastasis (LNM) at diagnosis was compared between screen-detected and non-screen-detected patients using multivariable logistic regression. Cox proportional hazard regression was used to analyze differences in the time to recurrence (TTR), metastasis-free survival (MFS), cancer-specific survival (CSS), and overall survival. Additionally, the performance of conventional risk factors for LNM was evaluated across the groups. RESULTS: 1803 patients were included (1114 [62%] screen-detected), with median follow-up of 51 months (interquartile range 30). The proportion of LNM did not significantly differ between screen- and non-screen-detected patients (12.6% vs. 8.9%; odds ratio 1.41; 95%CI 0.89-2.23); a prediction model for LNM performed equally in both groups. The 3- and 5-year TTR, MFS, and CSS were similar for patients within and outside the screening program. However, overall survival was significantly longer in screen-detected T1 CRC patients (adjusted hazard ratio 0.51; 95%CI 0.38-0.68). CONCLUSIONS: Screen-detected and non-screen-detected T1 CRCs have similar stage distributions and oncologic outcomes and can therefore be treated equally. However, screen-detected T1 CRC patients exhibit a lower rate of non-CRC-related mortality, resulting in longer overall survival.


Assuntos
Neoplasias Colorretais , Detecção Precoce de Câncer , Metástase Linfática , Estadiamento de Neoplasias , Humanos , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Neoplasias Colorretais/diagnóstico , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Detecção Precoce de Câncer/métodos , Países Baixos/epidemiologia , Fatores de Risco , Estudos Retrospectivos , Recidiva Local de Neoplasia , Modelos de Riscos Proporcionais , Colonoscopia/estatística & dados numéricos , Taxa de Sobrevida
12.
Anat Rec (Hoboken) ; 307(4): 851-889, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37589539

RESUMO

Proterochampsidae is a clade of non-archosaurian archosauriforms restricted to the Middle to the Late Triassic of the Ischigualasto-Villa Unión Basin of Argentina and the Santa Maria Supersequence of Brazil. A reappraisal of proterochampsid specimens from the Brazilian Dinodontosaurus Assemblage Zone (AZ) of the Pinheiros-Chiniquá Sequence (late Ladinian-early Carnian) is presented here. One of the specimens was preliminary assigned to Chanaresuchus sp., whose type species comes from the Massetognathus-Chanaresuchus AZ of the Chañares Formation of Argentina. However, our revision indicates that it differs from Chanaresuchus, being more closely related to the middle-late Carnian Rhadinosuchus gracilis. We therefore propose the new taxon, Pinheirochampsa rodriguesi, to reallocate this specimen. Additionally, we present a revision of other putative Chanaresuchus occurrences in Brazil, including the only known specimen described for the Santacruzodon AZ (Santa Cruz do Sul Sequence; early Carnian), also proposing it as a new taxon: Kuruxuchampsa dornellesi. Both new species are characterized, among other features, by transverse expansion of the anterior end of the rostrum, similar to the condition present in Rhadinosuchus, but absent in Chanaresuchus, Gualosuchus, Pseudochampsa, and non-rhadinosuchine proterochampsids. These two new species expand the growing knowledge of the non-archosaurian archosauriform diversity during the Middle-Late Triassic in South America and enhance faunal and chronological comparisons between approximately coeval geological units between Argentina and Brazil.


Assuntos
Dinossauros , Dente , Animais , Brasil , Fósseis , Argentina , Filogenia , Dinossauros/anatomia & histologia
13.
J Invest Dermatol ; 144(2): 316-330.e3, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37544588

RESUMO

Innate lymphoid cells (ILCs) are essential players in the skin-associated immune system, nevertheless little is known about their proteomes and proteomic diversity. In this study, we describe about 6,600 proteins constitutively expressed by ILC2s and ILC3s from healthy human skin and blood using state-of-the-art proteomics. Although the vast majority of proteins was expressed by both ILC subsets and in both compartments, the skin ILC2s and ILC3s were more distinct than their counterparts in blood. Only skin ILC3s expressed uniquely detected proteins. Our in-depth proteomic dataset allowed us to define the cluster of differentiation marker profiles of the ILC subsets, explore distribution and abundance of proteins known to have immunological functions, as well as identify subset-specific proteins that have not previously been implicated in ILC biology. Taken together, our analyses substantially expand understanding of the protein expression signatures of ILC subsets. Going forward, these proteomic datasets will serve as valuable resources for future studies of ILC biology.


Assuntos
Imunidade Inata , Linfócitos , Humanos , Proteômica , Pele
14.
J Sports Med Phys Fitness ; 63(11): 1194-1201, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37675501

RESUMO

BACKGROUND: Magnetic resonance imaging (MRI) is a well-used technique to assess muscle size and can be acquired on different planes. Pectoralis major (PM) and triceps brachii (TB) muscles are often acquired and analyzed on the axial plane, however it is unknown if anatomical cross-sectional area (CSA) calculated from different planes will affect the muscle size-strength relationship. Thus, the first aim of the present study was to identify if the CSA of the PM and TB measured on different planes presents a similar muscle size-strength relationship. A secondary aim was to investigate if the quantification of CSA of the PM and TB muscles are similar between sagittal and axial plane. METHODS: Fifteen males underwent an MRI examination, and after that, one-repetition maximum (1RM) test was performed. RESULTS: There was a significant relationship between 1RM and PM CSA measured on the axial and sagittal plane (r≤0.81), while the relationship with TB CSA was only good on the axial plane (r=0.65) and not significant on the sagittal plane (r=0.27). ICC between planes was excellent for PM CSA (0.96) with Bland-Altman procedure showing agreement between planes (d=0.376; P=0.612). Contrarily, TB CSA ICC was week (0.07), with Bland-Altman procedure showing no agreement between planes (d=-24.49; P=0.022). CONCLUSIONS: CSA measured at axial plane from PM and TB muscles showed a significant relationship with 1RM, while only PM CSA on the sagittal plane showed a significant relationship with 1RM. Finally, it was demonstrated that PM images showed a great reliability between planes, which was not true for TB muscle.


Assuntos
Músculo Esquelético , Músculos Peitorais , Masculino , Humanos , Músculos Peitorais/diagnóstico por imagem , Músculos Peitorais/fisiologia , Reprodutibilidade dos Testes , Músculo Esquelético/fisiologia , Braço , Força Muscular/fisiologia , Imageamento por Ressonância Magnética
15.
Pharmaceutics ; 15(8)2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37631236

RESUMO

Immunotherapy has changed the way many cancers are being treated. Researchers in the field of immunotherapy and tumor immunology are investigating similar questions: How can the positive benefits achieved with immunotherapies be enhanced? Can this be achieved through combinations with other agents and if so, which ones? In our view, there is an urgent need to improve immunotherapy to make further gains in the overall survival for those patients that should benefit from immunotherapy. While numerous different approaches are being considered, our team believes that drug delivery methods along with appropriately selected small-molecule drugs and drug candidates could help reach the goal of doubling the overall survival rate that is seen in some patients that are given immunotherapeutics. This review article is prepared to address how immunotherapies should be combined with a second treatment using an approach that could realize therapeutic gains 10 years from now. For context, an overview of immunotherapy and cancer angiogenesis is provided. The major targets in angiogenesis that have modulatory effects on the tumor microenvironment and immune cells are highlighted. A combination approach that, for us, has the greatest potential for success involves treatments that will normalize the tumor's blood vessel structure and alter the immune microenvironment to support the action of immunotherapeutics. So, this is reviewed as well. Our focus is to provide an insight into some strategies that will engender vascular normalization that may be better than previously described approaches. The potential for drug delivery systems to promote tumor blood vessel normalization is considered.

16.
Soft Matter ; 19(33): 6355-6367, 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37577849

RESUMO

It has been reported that lipid droplets (LDs), called oleosomes, have an inherent ability to inflate or shrink when absorbing or fueling lipids in the cells, showing that their phospholipid/protein membrane is dilatable. This property is not that common for membranes stabilizing oil droplets and when well understood, it could be exploited for the design of responsive and metastable droplets. To investigate the nature of the dilatable properties of the oleosomes, we extracted them from rapeseeds to obtain an oil-in-water emulsion. Initially, we added an excess of rapeseed oil in the dispersion and applied high-pressure homogenization, resulting in a stable oil-in-water emulsion, showing the ability of the molecules on the oleosome membrane to rearrange and reach a new equilibrium when more surface was available. To confirm the rearrangement of the phospholipids on the droplet surface, we used molecular dynamics simulations and showed that the fatty acids of the phospholipids are solubilized in the oil core and are homogeneously spread on the liquid-like membrane, avoiding clustering with neighbouring phospholipids. The weak lateral interactions on the oleosome membrane were also confirmed experimentally, using interfacial rheology. Finally, to investigate whether the weak lateral interactions on the oleosome membrane can be used to have a triggered change of conformation by an external force, we placed the oleosomes on a solid hydrophobic surface and found that they destabilise, allowing the oil to leak out, probably due to a reorganisation of the membrane phospholipids after their interaction with the hydrophobic surface. The weak lateral interactions on the LD membrane and their triggered destabilisation present a unique property that can be used for a targeted release in foods, pharmaceuticals and cosmetics.


Assuntos
Gotículas Lipídicas , Fosfolipídeos , Gotículas Lipídicas/química , Emulsões/química , Fosfolipídeos/química , Conformação Molecular , Água/química
17.
HPB (Oxford) ; 25(11): 1438-1445, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37550169

RESUMO

INTRODUCTION: Endoscopic ultrasonography guided tissue acquisition (EUS + TA) is used to provide a tissue diagnosis in patients with suspected pancreatic cancer. Key performance indicators (KPI) for these procedures are rate of adequate sample (RAS) and sensitivity for malignancy (SFM). AIM: assess practice variation regarding KPI of EUS + TA prior to resection of pancreatic carcinoma in the Netherlands. PATIENTS AND METHODS: Results of all EUS + TA prior to resection of pancreatic carcinoma from 2014-2018, were extracted from the national Dutch Pathology Registry (PALGA). Pathology reports were classified as: insufficient for analysis (b1), benign (b2), atypia (b3), neoplastic other (b4), suspected malignant (b5), and malignant (b6). RAS was defined as the proportion of EUS procedures yielding specimen sufficient for analysis. SFM was calculated using a strict definition (malignant only, SFM-b6), and a broader definition (SFM-b5+6). RESULTS: 691 out of 1638 resected patients (42%) underwent preoperative EUS + TA. RAS was 95% (range 89-100%), SFM-b6 was 44% (20-77%), and SFM-b5+6 was 65% (53-90%). All centers met the performance target RAS>85%. Only 9 out of 17 met the performance target SFM-b5+6 > 85%. CONCLUSION: This nationwide study detected significant practice variation regarding KPI of EUS + TA procedures prior to surgical resection of pancreatic carcinoma. Therefore, quality improvement of EUS + TA is indicated.

18.
Colloids Surf B Biointerfaces ; 229: 113476, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37499547

RESUMO

Oleosomes are natural oil droplets, present in all organisms and abundant in oilseeds. After their aqueous extraction from oilseeds, they can be directly utilized as oil droplets in food, cosmetics and all types of oil-in-water emulsion systems. However, to expand the potential uses of oleosomes as green ingredients and to valorize oilseeds as efficient as possible, we explored their emulsifying ability. Oleosomes were extracted from rapeseeds, and 10.0 wt% oil-in-water emulsions were created after homogenization with 0.5-6.0 wt% oleosomes, and the droplet size of the emulsions and their structure was measured by laser diffraction and confocal laser scanning microscopy (CLSM), respectively. The emulsion with an oleosome concentration lower than 1.0 wt% gave unstable emulsions with visible free oil. At oleosome concentrations at 1.5 wt% or higher, we obtained stable emulsions with droplet sizes between 2.0 and 12.0 µm. To investigate the role of the oleosome interfacial molecules in stabilizing emulsions we also studied their emulsifying and interfacial properties (using drop tensiometry) after isolating them from the oleosome structure. Both oleosomes and their isolated interfacial molecules exhibited a similar behavior on the oil-water interfaces, forming predominantly elastic interfacial films, and also showed a similar emulsifying ability. Our results show that oleosomes are not stabilizing the oil-in-water emulsions as intact particles, but they provide their interfacial molecules, which are enough to stabilize an oil-water surface up to about 2 times bigger than the initial oleosome surface. The understanding of the behavior of oleosomes as emulsifiers, opens many possibilities to use oleosomes as alternative to synthetic emulsifiers in food and pharma applications.


Assuntos
Emulsificantes , Gotículas Lipídicas , Emulsões/química , Emulsificantes/química , Água/química
19.
J Agric Food Chem ; 71(29): 11228-11238, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37433201

RESUMO

In isolates from different pea cultivars, the legumin-to-vicilin (L:V) ratio is known to vary from 66:33 to 10:90 (w/w). In this study, the effect of variations in the L:V ratio on the pea protein emulsifying properties (emulsion droplet size (d3,2) vs protein concentration (Cp)) at pH 7.0 was investigated using a purified pea legumin (PLFsol) and pea vicilin fraction (PVFsol). Despite a different Γmax,theo, the interfacial properties at the oil-water interface and the emulsifying properties were similar for PLFsol and PVFsol. Hence, the L:V ratio did not affect the pea protein emulsifying properties. Further, PLFsol and PVFsol were less efficient than whey protein isolate (WPIsol) in stabilizing the emulsion droplets against coalescence. This was explained by their larger radius and thus slower diffusion. For this reason, the difference in diffusion rate was added as a parameter to the surface coverage model. With this addition, the surface coverage model described the d3,2 versus Cp of the pea protein samples well.


Assuntos
Fabaceae , Proteínas de Ervilha , Pisum sativum/química , Emulsões/química , Proteínas de Ervilha/metabolismo , Proteínas/metabolismo , Verduras , Emulsificantes/química
20.
Bioresour Technol ; 382: 129169, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37187330

RESUMO

Tobacco stem is an abundant and inexpensive renewable source to produce prebiotics by circular economy. In this study, hydrothermal pretreatments were evaluated on the release of xylooligosaccharides (XOS) and cello-oligosaccharides (COS) from the tobacco stem by a central composite rotational design associated with response surface methodology to evaluate the effects of temperature (161.72 to 218.3 °C) and solid load (SL) (2.93 to 17.07%). XOS were the main compounds released to the liquor. Desirability function was performed to maximize the production of XOS and minimize the effects of release of monosaccharides and degradation compounds. The result indicated yield of 96% w[XOS]/w[xylan] for 190 °C-2.93% SL. The highest value for COS and total oligomers content (COS + XOS) was 6.42 g/L and 17.7 g/L, respectively, for 190 °C-17.07% SL. The mass balance for the best yield XOS condition predicted 132 kg of XOS (X2-X6) from 1000 kg of tobacco stem.


Assuntos
Nicotiana , Prebióticos , Hidrólise , Oligossacarídeos , Glucuronatos
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