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1.
Nutrition ; 123: 112426, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38581846

RESUMO

OBJECTIVE: Studies that have investigated the effect of nutritional counseling during the prenatal period on the follow-up outcomes of children at 6 mo have produced inconclusive results. The present study aimed to investigate the effect of nutritional counseling, based on the NOVA food classification, encouraging the consumption of fresh and minimally processed foods, with overweight adult pregnant women on infant growth at 6 mo of age. METHODS: A randomized controlled trial with 195 pairs of pregnant overweight women and their infants at 6 mo of age was conducted in a Brazilian municipality. The pregnant women were allocated to the control group (CG) or intervention group (IG) at the beginning of the pregnancy. The IG received three sessions of nutrition counseling throughout the pregnancy. Linear regression models were used to investigate the effect of the nutritional counseling on infant growth. RESULTS: One hundred ninety-five mother-infant pairs with complete data were included (96 CG, and 99 IG). The mean ± SD infant weight (g) at 6 mo was 7856.1 ± 1.1, and length (cm) was 67.0 ± 2.9. There were no differences in maternal and newborn characteristics between the groups. In the linear regression models, the counseling had no effect on anthropometric parameters of the infants at 6 mo of age: weight-for-length Z-score (ß 0.089 [95% CI -0.250; 0.427], P = 0.61); length-for-age Z-score (ß 0.032 [95% CI -0.299; 0.363], P = 0.85); weight-for-age Z-score (ß 0.070 [95% CI -0.260; 0.400], P = 0.68); BMI-age Z-score (ß 0.072 [95% CI -0.270; 0.414], P = 0.68). CONCLUSIONS: There was no effect on infant growth at 6 mo of age after the nutritional counseling during pregnancy. Future studies are needed to confirm this hypothesis.


Assuntos
Desenvolvimento Infantil , Aconselhamento , Sobrepeso , Humanos , Feminino , Gravidez , Lactente , Aconselhamento/métodos , Sobrepeso/terapia , Adulto , Brasil , Cuidado Pré-Natal/métodos , Complicações na Gravidez , Masculino , Fenômenos Fisiológicos da Nutrição Materna , Modelos Lineares
2.
Nanomedicine (Lond) ; 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38275157

RESUMO

Aim: Despite some successful examples of therapeutic nanoparticles reaching clinical stages, there is still a significant need for novel formulations in order to improve the selectivity and efficacy of cancer treatment. Methods: The authors developed two novel dendrimer-gold (Au) complex-based nanoparticles using two different synthesis routes: complexation method (formulation A) and precipitation method (formulation B). Using a biomimetic cancer-on-a-chip model, the authors evaluated the possible cytotoxicity and internalization by colorectal cancer cells of dendrimer-Au complex-based nanoparticles. Results: The results showed promising capabilities of these nanoparticles for selectively targeting cancer cells and delivering drugs, particularly for the formulation A nanoparticles. Conclusion: This work highlights the potential of dendrimer-Au complex-based nanoparticles as a new strategy to improve the targeting of anticancer drugs.

3.
Biofabrication ; 15(4)2023 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-37699408

RESUMO

Microfluidic organs and organoids-on-a-chip models of human gastrointestinal systems have been established to recreate adequate microenvironments to study physiology and pathophysiology. In the effort to find more emulating systems and less costly models for drugs screening or fundamental studies, gastrointestinal system organoids-on-a-chip have arisen as promising pre-clinicalin vitromodel. This progress has been built on the latest developments of several technologies such as bioprinting, microfluidics, and organoid research. In this review, we will focus on healthy and disease models of: human microbiome-on-a-chip and its rising correlation with gastro pathophysiology; stomach-on-a-chip; liver-on-a-chip; pancreas-on-a-chip; inflammation models, small intestine, colon and colorectal cancer organoids-on-a-chip and multi-organoids-on-a-chip. The current developments related to the design, ability to hold one or more 'organs' and its challenges, microfluidic features, cell sources and whether they are used to test drugs are overviewed herein. Importantly, their contribution in terms of drug development and eminent clinical translation in precision medicine field, Food and Drug Administration approved models, and the impact of organoid-on-chip technology in terms of pharmaceutical research and development costs are also discussed by the authors.


Assuntos
Trato Gastrointestinal , Sistemas Microfisiológicos , Estados Unidos , Humanos , Estômago , Fígado , Organoides
4.
Biofabrication ; 15(3)2023 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-36888998

RESUMO

Basic pre-clinical research based on 2D cultures have been very valuable in colorectal cancer (CRC) research but still have failed to improve patient prognostic outcomes. This is because they simply do not replicate what happensin vivo, i.e.2D cultured cells system cannot replicate the diffusion constraints usually found in the body. Importantly, they also do not mimic the dimensionality of the human body and of a CRC tumour (3D). Moreover, 2D cultures lack the cellular heterogeneity and the tumour microenvironment (TME) such as stromal components, blood vessels, fibroblasts, and cells of the immune system. Cells behave differently whether in 2D and 3D, in particular their different genetic and protein expression panels are very different and therefore we cannot fully rely on drug tests done in 2D. A growing field of research based on microphysiological systems involving organoids/spheroids or patient-derived tumour cells has become a solid base for a better understanding of the TME and as a result is a step towards personalized medicine. Furthermore, microfluidic approaches have also started to open possibilities of research, with tumour-on-chips and body-on-chips being used in order to decipher complex inter-organ signalling and the prevalence of metastasis, as well as CRC early-diagnosis through liquid biopsies. Herein, we focus on the state-of-the-art of CRC research with emphasis on 3D microfluidicin vitrocultures-organoids, spheroids-drug resistance, circulating tumour cells and microbiome-on-a-chip technology.


Assuntos
Neoplasias Colorretais , Sistemas Microfisiológicos , Humanos , Esferoides Celulares , Organoides , Fibroblastos , Microambiente Tumoral
5.
Pharmaceutics ; 14(11)2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36365226

RESUMO

(1) Background: Peripheral nerve injuries represent a major clinical challenge. If nerve ends retract, there is no spontaneous regeneration and grafts are required to proximate the nerve ends and give continuity to the nerve. (2) Methods: GDNF-loaded NPs were characterized physicochemically. For that, NPs stability at different pH's was assessed, and GDNF release was studied through ELISA. In vitro studies are performed with Schwann cells, and the NPs are labeled with fluorescein-5(6)-isothiocyanate for uptake experiments with SH-SY5Y neural cells. (3) Results: GDNF-loaded NPs are stable in physiological conditions, releasing GDNF in a two-step profile, which is beneficial for nerve repair. Cell viability is improved after 1 day of culture, and the uptake is near 99.97% after 3 days of incubation. (4) Conclusions: The present work shows the efficiency of using CMCht/PAMAM NPs as a GDNF-release system to act on peripheral nerve regeneration.

6.
Pharmacol Ther ; 239: 108276, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36055421

RESUMO

Digestive system cancers account for nearly half of all cancers around the world and have a high mortality rate. Cell culture and animal models represent cornerstones of digestive cancer research. However, their ability to enable cancer precision medicine is limited. Cell culture models cannot retain the genetic and phenotypic heterogeneity of tumors and lack tumor microenvironment (TME). Patient-derived xenograft mouse models are not suitable for immune-oncology research. While humanized mouse models are time- and cost-consuming. Suitable preclinical models, which can facilitate the understanding of mechanisms of tumor progression and develop new therapeutic strategies, are in high demand. This review article summarizes the recent progress on the establishment of TME by using tumor organoid models and microfluidic systems. The main challenges regarding the translation of organoid models from bench to bedside are discussed. The integration of organoids and a microfluidic platform is the emerging trend in drug screening and precision medicine. A future prospective on this field is also provided.


Assuntos
Neoplasias do Sistema Digestório , Neoplasias Gastrointestinais , Humanos , Animais , Camundongos , Medicina de Precisão , Organoides/patologia , Microambiente Tumoral , Neoplasias Gastrointestinais/patologia , Neoplasias do Sistema Digestório/patologia
7.
Int J Numer Method Biomed Eng ; 38(5): e3588, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35266291

RESUMO

Regular intestinal motility is essential to guarantee complete digestive function. The coordinative action and integrity of the smooth muscle layers in the small intestine's wall are critical for mixing and propelling the luminal content. However, some patients present gastrointestinal limitations which may negatively impact the normal motility of the intestine. These patients have altered mechanical and muscle properties that likely impact chyme propulsion and may pose a daily scenario for long-term complications. To better understand how mechanics affect chyme propulsion, the propulsive capability of the small intestine was examined during a peristaltic wave along the distal direction of the tract. It was assumed that such a wave works as an activation signal, inducing peristaltic contractions in a transversely isotropic hyperelastic model. In this work, the effect on the propulsion mechanics, from an impairment on the muscle contractile ability, typical from patients with systemic sclerosis, and the presence of sores resultant from ulcers was evaluated. The passive properties of the constitutive model were obtained from uniaxial tensile tests from a porcine small intestine, along with both longitudinal and circumferential directions. Our experiments show decreased stiffness in the circumferential direction. Our simulations show decreased propulsion forces in patients in systemic sclerosis and ulcer patients. As these patients may likely need medical intervention, establishing action concerning the impaired propulsion can help to ease the evaluation and treatment of future complications.


Assuntos
Peristaltismo , Escleroderma Sistêmico , Animais , Motilidade Gastrointestinal/fisiologia , Humanos , Intestino Delgado/fisiologia , Contração Muscular/fisiologia , Peristaltismo/fisiologia , Suínos
8.
Adv Exp Med Biol ; 1230: 121-135, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32285368

RESUMO

Microfluidic devices are now one of the most promising tools to mimic in vivo like conditions, either in normal or disease scenarios, such as tumorigenesis or pathogenesis. Together with the potential of biomaterials, its combination with microfluidics represents the ability to more closely mimic cells' natural microenvironment concerning its three-dimensional (3D) nature and continuous perfusion with nutrients and cells' crosstalk. Due to miniaturization and increased experimental throughput, microfluidics have generated significant interest in the drug discovery and development domain. Herein, the most recent advances in the field of microfluidics for drug discovery are overviewed, and the role of biomaterials in 3D in vitro models and the contribution of organ-on-a-chip technologies highlighted.


Assuntos
Materiais Biocompatíveis , Desenvolvimento de Medicamentos , Descoberta de Drogas , Dispositivos Lab-On-A-Chip , Microfluídica , Humanos , Miniaturização
9.
Adv Exp Med Biol ; 1059: 353-371, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29736582

RESUMO

Tissue engineering strategies have been pushing forward several fields in the range of biomedical research. The musculoskeletal field is not an exception. In fact, tissue engineering has been a great asset in the development of new treatments for osteochondral lesions. Herein, we overview the recent developments in osteochondral tissue engineering. Currently, the treatments applied in a clinical scenario have shown some drawbacks given the difficulty in regenerating a fully functional hyaline cartilage. Among the different strategies designed for osteochondral regeneration, it is possible to identify cell-free strategies, scaffold-free strategies, and advanced strategies, where different materials are combined with cells. Cell-free strategies consist in the development of scaffolds in the attempt to better fulfill the requirements of the cartilage regeneration process. For that, different structures have been designed, from monolayers to multilayered structures, with the intent to mimic the osteochondral architecture. In the case of scaffold-free strategies, they took advantage on the extracellular matrix produced by cells. The last strategy relies in the development of new biomaterials capable of mimicking the extracellular matrix. This way, the cell growth, proliferation, and differentiation at the lesion site are expedited, exploiting the self-regenerative potential of cells and its interaction with biomolecules. Overall, despite the difficulties associated with each approach, tissue engineering has been proven a valuable tool in the regeneration of osteochondral lesions and together with the latest advances in the field, promises to revolutionize personalized therapies.


Assuntos
Doenças Ósseas/cirurgia , Doenças das Cartilagens/cirurgia , Medicina Regenerativa/métodos , Engenharia Tecidual/métodos , Materiais Biocompatíveis/uso terapêutico , Materiais Biomiméticos/uso terapêutico , Doenças Ósseas/terapia , Doenças das Cartilagens/terapia , Condrócitos/transplante , Condrogênese , Matriz Extracelular , Humanos , Hidrogéis/uso terapêutico , Polissacarídeos/uso terapêutico , Medicina de Precisão , Impressão Tridimensional , Alicerces Teciduais
10.
Drug Discov Today ; 23(3): 711-718, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29337200

RESUMO

The development of tissue-engineering (TE) solutions for osteochondral (OC) regeneration has been slowed by technical hurdles related to the recapitulation of their complex and hierarchical architecture. OC defects refer to damage of both the articular cartilage and the underlying subchondral bone. To repair an OC tissue defect, the complexity of the bone and cartilage must be considered. To help achieve this, microfluidics is converging with TE approaches to provide new treatment possibilities. Microfluidics uses precise micrometer-to-millimeter-scale fluid flows to achieve high-resolution and spatial and/or temporal control of the cell microenvironment, providing powerful tools for cell culturing. Herein, we overview the progress of microfluidics for developing 3D in vitro models of OC tissue, with a focus on cancer bone metastasis.


Assuntos
Regeneração Óssea/fisiologia , Osso e Ossos/patologia , Cartilagem Articular/patologia , Animais , Biomimética/métodos , Descoberta de Drogas/métodos , Humanos , Microfluídica/métodos , Engenharia Tecidual/métodos , Alicerces Teciduais
11.
Glob Chall ; 2(5-6): 1700100, 2018 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-31565332

RESUMO

Microfluidic devices are now the most promising tool to mimic in vivo like scenarios such as tumorigenesis and metastasis due to its ability to more closely mimic cell's natural microenvironment (such as 3D environment and continuous perfusion of nutrients). In this study, the ability of 2% and 3% enzymatically crosslinked silk fibroin hydrogels with different mechanical properties are tested in terms of colorectal cancer cell migration, under different microenvironments in a 3D dynamic model. Matrigel is used as control. Moreover, a comprehensive comparison between the traditional Boyden chamber assay and the 3D dynamic microfluidic model in terms of colorectal cancer cell migration is presented. The results show profound differences between the two used biomaterials and the two migration models, which are explored in terms of mechanical properties of the hydrogels as well as the intrinsic characteristics of the models. Moreover, the developed 3D dynamic model is validated by demonstrating that hVCAM-1 plays a major role in the extravasation process, influencing extravasation rate and traveled distance. Furthermore, the developed model enables precise visualization of cancer cell migration within a 3D matrix in response to microenvironmental cues, shedding light on the importance of biophysical properties in cell behavior.

12.
Stem Cell Rev Rep ; 13(3): 347-363, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28233276

RESUMO

Drug toxicity frequently goes concealed until clinical trials stage, which is the most challenging, dangerous and expensive stage of drug development. Both the cultures of cancer cells in traditional 2D assays and animal studies have limitations that cannot ever be unraveled by improvements in drug-testing protocols. A new generation of bioengineered tumors is now emerging in response to these limitations, with potential to transform drug screening by providing predictive models of tumors within their tissue context, for studies of drug safety and efficacy. Considering the NCI60, a panel of 60 cancer cell lines representative of 9 different cancer types: leukemia, lung, colorectal, central nervous system (CNS), melanoma, ovarian, renal, prostate and breast, we propose to review current "state of art" on the 9 cancer types specifically addressing the 3D tissue models that have been developed and used in drug discovery processes as an alternative to complement their study.


Assuntos
Antineoplásicos , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Modelos Biológicos , Neoplasias/tratamento farmacológico , Engenharia Tecidual/métodos , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Humanos , Neoplasias/metabolismo , Neoplasias/patologia
13.
Nanomedicine (Lond) ; 12(6): 581-596, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28186438

RESUMO

AIM: Develop a platform composed of labeled dendrimer nanoparticles (NPs) and a microfluidic device for real-time monitoring of cancer cells fate. MATERIALS & METHODS: Carboxymethylchitosan/poly(amidoamine) dendrimer NPs were labeled with fluorescein-5(6)-isothiocyanate and characterized using different physicochemical techniques. After, HeLa, HCT-116 and U87MG were cultured in the presence of NPs, and cell viability and internalization efficiency in static (standard culture) and dynamic (microfluidic culture) conditions were investigated. RESULTS: Cancer cells cultured with NPs in dynamic conditions were viable and presented higher internalization levels as compared with static 2D cultures. CONCLUSION: This work demonstrated that the proposed microfluidic-based platform allows real-time monitoring, which upon more studies, namely, the assessment of an anticancer drug release effect could be used for cancer theranostics.


Assuntos
Portadores de Fármacos/química , Microfluídica/métodos , Nanopartículas/química , Neoplasias/tratamento farmacológico , Sobrevivência Celular/efeitos dos fármacos , Quitosana/administração & dosagem , Quitosana/análogos & derivados , Quitosana/química , Dendrímeros/administração & dosagem , Dendrímeros/química , Portadores de Fármacos/administração & dosagem , Endocitose/efeitos dos fármacos , Células HeLa , Humanos , Nanopartículas/administração & dosagem
14.
Trends Biotechnol ; 33(11): 667-678, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26603572

RESUMO

Cancer is a major cause of morbidity and mortality worldwide, with a disease burden estimated to increase over the coming decades. Disease heterogeneity and limited information on cancer biology and disease mechanisms are aspects that 2D cell cultures fail to address. Here, we review the current 'state-of-the-art' in 3D tissue-engineering (TE) models developed for, and used in, cancer research. We assess the potential for scaffold-based TE models and microfluidics to fill the gap between 2D models and clinical application. We also discuss recent advances in combining the principles of 3D TE models and microfluidics, with a special focus on biomaterials and the most promising chip-based 3D models.


Assuntos
Microfluídica/métodos , Modelos Biológicos , Neoplasias/fisiopatologia , Engenharia Tecidual/métodos , Humanos
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