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1.
Ir J Med Sci ; 2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-39030461

RESUMO

Acute promyelocytic leukaemia (APL) with a STAT5b::RARα gene fusion is an extremely rare subtype of APL characterised by resistance to conventional therapies and extremely poor prognosis. This case highlights that whilst APL with variant RARα translocations are rare, they do pose significant challenges both diagnostically and in their clinical management. This case, in the first instance, demonstrates the importance of using a combination of molecular techniques including next generation sequencing (NGS) for diagnosis particularly in morphological and immunophenotypic typical APL which appears negative by confirmatory testing. Secondly, our patient represents, to the best of our knowledge, the first documented example of this rare disease that has been managed with, and shown sensitivity to low-dose cytarabine (LDAC) in combination with venetoclax (Ven). This case demonstrates that although treatment options are extremely limited for patients not eligible for intensive chemotherapy non-intensive options do show increasing promise.

2.
Int J Nanomedicine ; 19: 3623-3639, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38660023

RESUMO

Introduction: Despite improvements in chemotherapy and molecularly targeted therapies, the life expectancy of patients with advanced non-small cell lung cancer (NSCLC) remains less than 1 year. There is thus a major global need to advance new treatment strategies that are more effective for NSCLC. Drug delivery using liposomal particles has shown success at improving the biodistribution and bioavailability of chemotherapy. Nevertheless, liposomal drugs lack selectivity for the cancer cells and have a limited ability to penetrate the tumor site, which severely limits their therapeutic potential. Epidermal growth factor receptor (EGFR) is overexpressed in NSCLC tumors in about 80% of patients, thus representing a promising NSCLC-specific target for redirecting liposome-embedded chemotherapy to the tumor site. Methods: Herein, we investigated the targeting of PEGylated liposomal doxorubicin (Caelyx), a powerful off-the-shelf antitumoral liposomal drug, to EGFR as a therapeutic strategy to improve the specific delivery and intratumoral accumulation of chemotherapy in NSCLC. EGFR-targeting of Caelyx was enabled through its complexing with a polyethylene glycol (PEG)/EGFR bispecific antibody fragment. Tumor targeting and therapeutic potency of our treatment approach were investigated in vitro using a panel of NSCLC cell lines and 3D tumoroid models, and in vivo in a cell line-derived tumor xenograft model. Results: Combining Caelyx with our bispecific antibody generated uniform EGFR-targeted particles with improved binding and cytotoxic efficacy toward NSCLC cells. Effects were exclusive to cancer cells expressing EGFR, and increments in efficacy positively correlated with EGFR density on the cancer cell surface. The approach demonstrated increased penetration within 3D spheroids and was effective at targeting and suppressing the growth of NSCLC tumors in vivo while reducing drug delivery to the heart. Conclusion: EGFR targeting represents a successful approach to enhance the selectivity and therapeutic potency of liposomal chemotherapy toward NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Doxorrubicina , Receptores ErbB , Neoplasias Pulmonares , Animais , Feminino , Humanos , Camundongos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Linhagem Celular Tumoral , Doxorrubicina/química , Doxorrubicina/farmacologia , Doxorrubicina/farmacocinética , Doxorrubicina/análogos & derivados , Doxorrubicina/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Receptores ErbB/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Camundongos Nus , Polietilenoglicóis/química , Polietilenoglicóis/farmacocinética , Distribuição Tecidual , Ensaios Antitumorais Modelo de Xenoenxerto
3.
J Control Release ; 367: 806-820, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38341177

RESUMO

High-risk neuroblastoma has poor survival due to treatment failure and off-target side effects of therapy. Small molecule inhibitors have shown therapeutic efficacy at targeting oncogenic cell cycle dysregulators, such as polo-like kinase 1 (PLK1). However, their clinical success is limited by a lack of efficacy and specificity, causing off-target toxicity. Herein, we investigate a new treatment strategy whereby a bispecific antibody (BsAb) with dual recognition of methoxy polyethylene glycol (PEG) and a neuroblastoma cell-surface receptor, epidermal growth factor receptor (EGFR), is combined with a PEGylated small interfering RNA (siRNA) lipid nanoparticle, forming BsAb-nanoparticle RNA-interference complexes for targeted PLK1 inhibition against high-risk neuroblastoma. Therapeutic efficacy of this strategy was explored in neuroblastoma cell lines and a tumor xenograft model. Using ionizable lipid-based nanoparticles as a low-toxicity and clinically safe approach for siRNA delivery, we identified that their complexing with EGFR-PEG BsAb resulted in increases in cell targeting (1.2 to >4.5-fold) and PLK1 gene silencing (>2-fold) against EGFR+ high-risk neuroblastoma cells, and enhancements correlated with EGFR expression on the cells (r > 0.94). Through formulating nanoparticles with PEG-lipids ranging in diffusivity, we further identified a highly diffusible PEG-lipid which provided the most pronounced neuroblastoma cell binding, PLK1 silencing, and significantly reduced cancer growth in vitro in high-risk neuroblastoma cell cultures and in vivo in a tumor-xenograft mouse model of the disease. Together, this work provides an insight on the role of PEG-lipid diffusivity and EGFR targeting as potentially relevant variables influencing the therapeutic efficacy of siRNA nanoparticles in high-risk neuroblastoma.


Assuntos
Nanopartículas , Neuroblastoma , Humanos , Animais , Camundongos , RNA Interferente Pequeno , Proteínas Serina-Treonina Quinases , Proteínas de Ciclo Celular/genética , Quinase 1 Polo-Like , Polietilenoglicóis/química , Proteínas Proto-Oncogênicas , Linhagem Celular Tumoral , Neuroblastoma/tratamento farmacológico , Receptores ErbB/genética , Nanopartículas/química , Proliferação de Células , Lipídeos/farmacologia
4.
Adv Food Nutr Res ; 105: 221-254, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37516464

RESUMO

The processes for extracting and refining edible oils are well-established in industry at different scales. However, these processing lines encounter inefficiencies and oil losses when recovering crude or refined oil. Palm oil and olive oil extraction methods are used mainly as a combination of physical, thermal, and centrifugal methods to recover crude oil, which results in oil losses in the olive pomace or in palm oil effluents. Seed oils generally require a seed steam conditioning, and cooking stage, followed by physical oil recovery through an inefficient expeller. Most of the crude oil remaining in the expeller cake is then recovered by hexane. Crude seed oil is further refined in stages that also undergo oil losses. This chapter provides an overview of innovative technologies using microwave, ultrasound, megasonic and pulsed electric field energies, which can be used in the above-mentioned crude and refined oil processes to improve oil recovery. This chapter describes traditional palm oil, olive oil, and seed oil processes, as well as the specific process interventions that have been tested with these technologies. The impact of such technology interventions on oil quality is also summarized.


Assuntos
Petróleo , Azeite de Oliva , Óleo de Palmeira , Indústrias Extrativas e de Processamento
5.
Sci Rep ; 10(1): 12299, 2020 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-32704146

RESUMO

Milk fat globule (MFG) size is a milk production trait characteristic to the individual animal and has important effects on the functional and nutritional properties of milk. Although the regulation of MFG size in the mammary epithelial cell is not fully understood, lipid droplet (LD) fusion prior to secretion is believed to play a role. We selected cows that consistently produced milk with predominantly small or large MFGs to compare their lipidomic profiles, with focus on the polar lipid fraction. The polar lipid composition of the monolayer surrounding the LD is believed to either promote or prevent LD fusion. Using a targeted LC-MS/MS approach we studied the relative abundance of 301 detected species and found significant differences between the studied groups. Here we show that the lipidomic profile of milk from small MFG cows is characterised by higher phosphatidylcholine to phosphatidylethanolamine ratios. In contrast, the milk from large MFG cows contained more ether-phosphatidylethanolamine species. This is the first time that a potential role for ether-phosphatidylethanolamine in MFG size development has been suggested.


Assuntos
Células Epiteliais/metabolismo , Glicolipídeos/metabolismo , Glicoproteínas/metabolismo , Gotículas Lipídicas/metabolismo , Glândulas Mamárias Animais/metabolismo , Fosfatidiletanolaminas/metabolismo , Característica Quantitativa Herdável , Animais , Bovinos , Cromatografia Líquida , Feminino , Metabolismo dos Lipídeos , Lipidômica/métodos , Redes e Vias Metabólicas , Espectrometria de Massas em Tandem
6.
In Vitro Cell Dev Biol Anim ; 56(5): 386-398, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32472301

RESUMO

This study aimed to establish an in vitro model for lipid synthesis in primary bovine mammary epithelial cells (pbMECs) extracted from milk and cultured on Transwell permeable supports (TW culture). The suitability of these cells as a functional model for lactation was assessed by measuring κ-casein (CSN3) and diacylglycerol acyl transferase 1 (DGAT1) gene expression, the presence of intracellular lipid droplets, and the concentration of triacylglycerol in the cell lysates. The functionality of the milk-derived pbMECs cultured under lactogenic conditions, with and without oleic acid supplementation, was evaluated by comparing the cells grown on Transwell supports to cells grown on an extracellular matrix (ECM) gel (3D culture) or a plastic surface (2D culture). Furthermore, the functionality of milk-derived cells was compared to pbMECs obtained from bovine mammary tissue. Here, we show that in both tissue and milk-derived pbMECs, 3D culture offered the most suitable in vitro environment and led to increased levels of CSN3 and DGAT1 gene expression along with increased intracellular triacylglycerol content. The TW culture conditions also resulted in increased DGAT1 gene expression compared to the 2D conditions and milk-derived pbMECs cultured on TW inserts showed the highest viability compared to cells grown under 2D or 3D treatments. However, this was not observed for tissue-derived pbMECs, suggesting that TW culture may offer a beneficial environment specifically for milk-derived cells. We suggest that with further optimization of the culture conditions, TW culture may present a suitable model for the study of milk lipid synthesis in pbMECs.


Assuntos
Células Epiteliais/citologia , Lactação , Glândulas Mamárias Animais/citologia , Membranas Artificiais , Leite/citologia , Modelos Biológicos , Animais , Caseínas/genética , Caseínas/metabolismo , Bovinos , Polaridade Celular , Proliferação de Células , Sobrevivência Celular , Diacilglicerol O-Aciltransferase/genética , Diacilglicerol O-Aciltransferase/metabolismo , Impedância Elétrica , Feminino , Queratina-8/genética , Queratina-8/metabolismo , Permeabilidade , Triglicerídeos/metabolismo
7.
Food Chem ; 264: 24-33, 2018 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-29853371

RESUMO

Phytosterols can lower LDL-cholesterol and are frequently used by the functional food industry. However, little is known regarding how phytosterol crystallisation can be controlled, despite solubilised phytosterols having improved bioaccessibility. This study investigates phytosterol crystallisation in bulk milk fat and in model dairy emulsion systems at two average droplet sizes, 1.0 and 0.2 µm. The effect of lecithin and monoacylglycerol addition on phytosterol crystallisation for both emulsion and bulk systems was also evaluated. Results demonstrated that lecithin and monoacylglycerols enrichment into the bulk system minimised phytosterol crystallisation. However, in emulsions, phytosterol crystallisation was mainly influenced by decreasing the droplet size. Smaller emulsion droplets containing lecithin showed the greatest potential for decreasing phytosterol crystallisation and had improved physicochemical stability. This information can be employed by the functional food industry to minimise phytosterol crystallisation and possibly improve bioaccessibility.


Assuntos
Emulsões/química , Leite/química , Fitosteróis/química , Triglicerídeos/química , Animais , Cristalização , Lecitinas/química , Microscopia de Polarização , Peso Molecular , Tensoativos/química
8.
J Agric Food Chem ; 64(34): 6546-54, 2016 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-27476512

RESUMO

Milk has been used commercially as a carrier for phytosterols, but there is limited knowledge on the effect of added plant sterols on the properties of the system. In this study, phytosterols dispersed in milk fat at a level of 0.3 or 0.6% were homogenized with an aqueous dispersion of whey protein isolate (WPI). The particle size, morphology, ζ-potential, and stability of the emulsions were investigated. Emulsion crystallization properties were examined through the use of differential scanning calorimetry (DSC) and Synchrotron X-ray scattering at both small and wide angles. Phytosterol enrichment influenced the particle size and physical appearance of the emulsion droplets, but did not affect the stability or charge of the dispersed particles. DSC data demonstrated that, at the higher level of phytosterol addition, crystallization of milk fat was delayed, whereas, at the lower level, phytosterol enrichment induced nucleation and emulsion crystallization. These differences were attributed to the formation of separate phytosterol crystals within the emulsions at the high phytosterol concentration, as characterized by Synchrotron X-ray measurements. X-ray scattering patterns demonstrated the ability of the phytosterol to integrate within the milk fat triacylglycerol matrix, with a concomitant increase in longitudinal packing and system disorder. Understanding the consequences of adding phytosterols, on the physical and crystalline behavior of emulsions may enable the functional food industry to design more physically and chemically stable products.


Assuntos
Gorduras/química , Leite/química , Fitosteróis/química , Animais , Varredura Diferencial de Calorimetria , Bovinos , Cristalização , Emulsões/química , Óleos/química , Tamanho da Partícula , Água/química
9.
J Food Sci ; 78(9): C1340-7, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24024687

RESUMO

International dietary guidelines advocate replacement of saturated and trans fat in food with unsaturated oils. Also, there is growing interest in incorporating highly unsaturated omega-3 oils in to food products due to beneficial health effects. A major obstacle to incorporating highly unsaturated oils in to food products is the extreme susceptibility to oxidative deterioration. Oil bodies were prepared from tuna oil, oleosin, and phospholipid mimicking natural oil bodies within oilseed. Oleosin was extracted from canola (Brassica napus) meal by solubilization in aqueous sodium hydroxide (pH 12) and subsequent precipitation at its isoelectric point of pH 6.5. The tuna oil artificial oil bodies (AOBs) readily dispersed in water to produce oil-in-water (o/w) emulsions, which did not coalesce on storage and were amenable to pasteurization using standard conditions. Accelerated oxidation studies showed that these AOB emulsions were substantially more resistant to lipid oxidation than o/w emulsions prepared from tuna oil using Tween40, sodium caseinate, and commercial canola protein isolate, respectively. There is potential to use commercial canola meal, which is cheap and abundant, as a natural source of oleosin for the preparation of physically and oxidatively stable food emulsions containing highly unsaturated oils.


Assuntos
Brassica rapa/química , Emulsões/química , Óleos de Peixe/química , Proteínas de Plantas/isolamento & purificação , Animais , Caseínas , Ácidos Graxos Ômega-3/análise , Manipulação de Alimentos/métodos , Concentração de Íons de Hidrogênio , Metabolismo dos Lipídeos , Estresse Oxidativo , Tamanho da Partícula , Proteínas de Plantas/química , Atum
10.
Med Oncol ; 27(3): 667-72, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19629764

RESUMO

An 86-year-old man presented with acute hepatic failure, worsening thrombocytopenia, and anemia having been diagnosed and managed expectantly with cytogenetically normal RAEB-1. After 20 months a diagnosis of disease transformation to acute monocytic leukemia (M5b) was made. Conventional G-banded analysis of unstimulated bone marrow cultures demonstrated a jumping translocation (JT) involving proximal and distal breakpoints on donor chromosome 3 at bands 3q1?2 and 3q21, respectively. Recipient chromosomes included the long-arm telomeric regions of chromosomes 5, 10, 14, 16, and 19. A low-level trisomy 8 clone was also found in association with both proximal and distal JT clones. Conventional G-banded analysis of unstimulated peripheral blood cultures detected the proximal 3q1?2 JT clone involving recipient chromosome 10 several weeks after transformation to acute monocytic leukemia. Interestingly, JTs involving recipient chromosomes 5, 14, 16, and 19 were not detected in this peripheral blood sample. Palliative care was administered until his demise 2.2 months after disease transformation. There have been fewer than 70 cases of acquired JTs reported in the literature, including one myeloproliferative neoplasm and five acute myeloid leukemias involving a single breakpoint site on donor chromosome 3. Our case is unique as it is the first acquired case to demonstrate a JT involving alternative pericentromeric breakpoint sites on a single donor chromosome consisting of a proximal breakpoint at 3q1?2 and a more distal breakpoint at 3q21.


Assuntos
Pontos de Quebra do Cromossomo , Cromossomos Humanos Par 3/genética , Leucemia Monocítica Aguda/genética , Translocação Genética , Idoso de 80 Anos ou mais , Anemia Refratária com Excesso de Blastos/genética , Cromossomos Humanos Par 3/ultraestrutura , Progressão da Doença , Humanos , Masculino
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