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1.
Eur J Pharm Biopharm ; 198: 114266, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38499255

RESUMO

Design of inhalable mRNA therapeutics is promising because local administration in the respiratory tract is minimally invasive and induces a local response. However, several challenges related to administration via inhalation and respiratory tract barriers have so far prevented the progress of inhaled mRNA therapeutics. Here, we investigated factors of importance for lipid nanoparticle (LNP)-mediated delivery of mRNA to the respiratory tract. We hypothesized that: (i) the PEG-lipid content is important for providing colloidal stability during aerosolization and for mucosal delivery, (ii) the PEG-lipid contentinfluences the expression of mRNA-encoded protein in the lungs, and (iii) the route of administration (nasal versus pulmonary) affects mRNA delivery in the lungs. In this study, we aimed to optimize the PEG-lipid content for mucosal delivery and to investigatethe effect of administration route on the kinetics of protein expression. Our results show that increasing the PEG-lipid content improves the colloidal stability during the aerosolization process, but has a negative impact on the transfection efficiencyin vitro. The kinetics of protein expressionin vivois dependent on the route of administration, and we found that pulmonaryadministration of mRNA-LNPs to mice results inmore durable protein expression than nasaladministration. These results demonstrate that the design of the delivery system and the route of administration are importantfor achieving high mRNA transfection efficiency in the respiratory tract.


Assuntos
Nanopartículas , Sistema Respiratório , Animais , Camundongos , Lipossomos , RNA Mensageiro , Lipídeos
2.
J Colloid Interface Sci ; 660: 66-76, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38241872

RESUMO

The development of lipid nanoparticle (LNP) based therapeutics for delivery of RNA has triggered the advance of new strategies for formulation, such as high throughput microfluidics for precise mixing of components into well-defined particles. In this study, we have characterised the structure of LNPs throughout the formulation process using in situ small angle x-ray scattering in the microfluidic chip, then by sampling in the subsequent dialysis process. The final formulation was investigated with small angle x-ray (SAXS) and neutron (SANS) scattering, dynamic light scattering (DLS) and cryo-TEM. The effect on structure was investigated for LNPs with a benchmark lipid composition and containing different cargos: calf thymus DNA (DNA) and two model mRNAs, polyadenylic acid (polyA) and polyuridylic acid (polyU). The LNP structure evolved during mixing in the microfluidic channel, however was only fully developed during the dialysis. The colloidal stability of the final formulation was affected by the type of incorporated nucleic acids (NAs) and decreased with the degree of base-pairing, as polyU induced extensive particle aggregation. The main NA LNP peak in the SAXS data for the final formulation were similar, with the repeat distance increasing from polyU

Assuntos
Lipídeos , Lipossomos , Nanopartículas , Espalhamento a Baixo Ângulo , Lipídeos/química , Difração de Raios X , Nanopartículas/química , DNA , RNA Mensageiro , RNA Interferente Pequeno/química
3.
Int J Surg ; 110(1): 395-405, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37737933

RESUMO

The ongoing global health challenge of cancer is driving the pursuit of innovative avenues for prevention, treatment, and enhanced outcomes. The convergence of nutrition and immune modulation, known as immunonutrition, is ready to act as a catalyst for transformative change in cancer research and therapy. Our study employs a bibliometric analysis to uncover the evolving trends within immunonutrition and cancer research across the past 25 years. Bibliometric data, including authors, journals, affiliations, and countries, were analyzed using the Bibliometrix R package. Clustering algorithms were applied to keywords to identify thematic areas and their evolution. A total of 489 documents were analyzed, showing an annual growth rate of 8.7%, with a collaboration index of 5.41, highlighting comprehensive multidisciplinary involvement within this landscape. Core authors demonstrated sustained productivity, while occasional authors indicated widespread interest. The Medical University of Warsaw led in institutional contributions. Country-wise, Italy, France, and the USA emerged as forerunners in fostering research productivity. Key journals like 'Clinical Nutrition' served as beacons, emphasizing the multidimensional nature of this topic. The analysis highlighted growing research output and several collaborations, indicating the importance of immunoenriched nutrition in cancer treatment. The interplay of core authors and diversified engagement harmoniously accentuates the cross-disciplinary nature of this burgeoning field. International collaboration facilitated knowledge exchange. Prominent documents shaped the field, emphasizing the significance of nutritional interventions. Thematic clusters revealed varied focuses, including pharmaconutrients, surgical approaches, inflammation, and specific cancers. The expanding research output suggests further development, particularly in exploring immunoenriched nutrition's impact on cancer types and patient populations. The multidisciplinary nature and international collaborations enhance the field's progress. Gaps in research underscore the need for original studies and personalized approaches. This study guides future research, informing evidence-based nutritional interventions and advancing cancer care practices.


Assuntos
Dieta de Imunonutrição , Neoplasias , Humanos , Algoritmos , Bibliometria , Análise por Conglomerados , França , Neoplasias/terapia
4.
Nanoscale Adv ; 4(21): 4526-4534, 2022 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-36341300

RESUMO

Supported lipid bilayers (SLBs) are commonly used as model systems mimicking biological membranes. Recently, we reported a new method to produce SLBs with incorporated membrane proteins, which is based on the application of peptide discs [Luchini et al., Analytical Chemistry, 2020, 92, 1081-1088]. Peptide discs are small discoidal particles composed of a lipid core and an outer belt of self-assembled 18A peptides. SLBs including membrane proteins can be formed by depositing the peptide discs on a solid support and subsequently removing the peptide by buffer rinsing. Here, we introduce a new variant of the 18A peptide, named dark peptide (d18A). d18A exhibits UV absorption at 214 nm, whereas the absorption at 280 nm is negligible. This improves sample preparation as it enables a direct quantification of the membrane protein concentration in the peptide discs by measuring UV absorption at 280 nm. We describe the application of the peptide discs prepared with d18A (dark peptide discs) to produce SLBs with a membrane protein, synaptobrevin 2 (VAMP2). The collected data showed the successful formation of SLBs with high surface coverage and incorporation of VAMP2 in a single orientation with the extramembrane domain exposed towards the bulk solvent. Compared to 18A, we found that d18A was more efficiently removed from the SLB. Our data confirmed the structural organisation of VAMP2 as including both α-helical and ß-sheet secondary structure. We further verified the orientation of VAMP2 in the SLBs by characterising the binding of VAMP2 with α-synuclein. These results point at the produced SLBs as relevant membrane models for biophysical studies as well as nanostructured biomaterials.

5.
Front Nutr ; 9: 978271, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36185669

RESUMO

Preterm newborn infants are characterized by low body weight and lower fat mass at birth compared with full-term newborn neonates. Conversely, at term corrected age, body fat mass is more represented in preterm newborn infants, causing a predisposition to developing metabolic syndrome and cardiovascular diseases in later life with a different risk profile in men as compared with women. Postnatal growth is a complex change in anthropometric parameters and body composition. Both quantity and quality of growth are regulated by several factors such as fetal programming, early nutrition, and gut microbiota. Weight gain alone is not an optimal indicator of nutritional status as it does not accurately describe weight quality. The analysis of body composition represents a potentially useful tool to predict later metabolic and cardiovascular risk as it detects the quality of growth by differentiating between fat and lean mass. Longitudinal follow-up of preterm newborn infants could take advantage of body composition analysis in order to identify high-risk patients who apply early preventive strategies. This narrative review aimed to examine the state-of-the-art body composition among born preterm children, with a focus on those in the pre-school age group.

6.
J Colloid Interface Sci ; 610: 766-774, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34848062

RESUMO

Lipid nanoparticles (LNPs) are promising drug and gene carriers. Upon intravenous administration, LNPs' experience different degree of cellular uptake depending on their formulation. Currently, in vitro and in vivo studies are the gold standard for assessing the fate of nano carriers once administered, but they are time consuming and expensive. In this work, we propose a time and cost-effective method to screen a wide range of LNP formulations and select the most promising candidates for in vitro and in vivo studies. Two different approaches were explored to investigate the binding affinity between LNPs and serum proteins using sensor functionalisation with either protein specific antibody or PEG specific antibody. The first approach allowed to identify the presence of a specific protein in the protein corona of lipid particles (reconstituted and native high-density lipoproteins (rHDL and HDL), and low-density lipoproteins LDL); while the second one provided a versatile platform for the immobilisation of pegylated-particles in order to follow the interaction with serum proteins and hence predict the composition of LNP protein corona. Sensing was done using Quartz Crystal Microbalance with Dissipation (QCM-D) but the approach is extendable to other surface sensing techniques such as Surface Plasmon Resonance (SPR) or ellipsometry.


Assuntos
Proteínas Sanguíneas/metabolismo , Lipídeos , Nanopartículas , Humanos , Lipossomos , Ligação Proteica
7.
Front Chem ; 9: 630152, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33996741

RESUMO

Apolipoprotein E (ApoE), an important mediator of lipid transportation in plasma and the nervous system, plays a large role in diseases such as atherosclerosis and Alzheimer's. The major allele variants ApoE3 and ApoE4 differ only by one amino acid. However, this difference has major consequences for the physiological behaviour of each variant. In this paper, we follow (i) the initial interaction of lipid-free ApoE variants with model membranes as a function of lipid saturation, (ii) the formation of reconstituted High-Density Lipoprotein-like particles (rHDL) and their structural characterisation, and (iii) the rHDL ability to exchange lipids with model membranes made of saturated lipids in the presence and absence of cholesterol [1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) or 1-palmitoyl-2-oleoyl-glycero-3-phosphocholine (POPC) with and without 20 mol% cholesterol]. Our neutron reflection results demonstrate that the protein variants interact differently with the model membranes, adopting different protein conformations. Moreover, the ApoE3 structure at the model membrane is sensitive to the level of lipid unsaturation. Small-angle neutron scattering shows that the ApoE containing lipid particles form elliptical disc-like structures, similar in shape but larger than nascent or discoidal HDL based on Apolipoprotein A1 (ApoA1). Neutron reflection shows that ApoE-rHDL do not remove cholesterol but rather exchange saturated lipids, as occurs in the brain. In contrast, ApoA1-containing particles remove and exchange lipids to a greater extent as occurs elsewhere in the body.

8.
ACS Nano ; 15(4): 6709-6722, 2021 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-33754708

RESUMO

Emerging therapeutic treatments based on the production of proteins by delivering mRNA have become increasingly important in recent times. While lipid nanoparticles (LNPs) are approved vehicles for small interfering RNA delivery, there are still challenges to use this formulation for mRNA delivery. LNPs are typically a mixture of a cationic lipid, distearoylphosphatidylcholine (DSPC), cholesterol, and a PEG-lipid. The structural characterization of mRNA-containing LNPs (mRNA-LNPs) is crucial for a full understanding of the way in which they function, but this information alone is not enough to predict their fate upon entering the bloodstream. The biodistribution and cellular uptake of LNPs are affected by their surface composition as well as by the extracellular proteins present at the site of LNP administration, e.g., apolipoproteinE (ApoE). ApoE, being responsible for fat transport in the body, plays a key role in the LNP's plasma circulation time. In this work, we use small-angle neutron scattering, together with selective lipid, cholesterol, and solvent deuteration, to elucidate the structure of the LNP and the distribution of the lipid components in the absence and the presence of ApoE. While DSPC and cholesterol are found to be enriched at the surface of the LNPs in buffer, binding of ApoE induces a redistribution of the lipids at the shell and the core, which also impacts the LNP internal structure, causing release of mRNA. The rearrangement of LNP components upon ApoE incubation is discussed in terms of potential relevance to LNP endosomal escape.


Assuntos
Nanopartículas , Apolipoproteínas E/genética , RNA Mensageiro/genética , RNA Interferente Pequeno/metabolismo , Distribuição Tecidual
9.
J Colloid Interface Sci ; 585: 376-385, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33307306

RESUMO

Supported lipid bilayers (SLBs) are commonly used to investigate the structure and dynamics of biological membranes. Vesicle fusion is a widely exploited method to produce SLBs. However, this process becomes less favoured when the vesicles contain complex lipid mixtures, e.g. natural lipid extracts. In these cases, it is often necessary to change experimental parameters, such as temperature, to unphysiological values to trigger the SLB formation. This may induce lipid degradation and is also not compatible with including membrane proteins or other biomolecules into the bilayers. Here, we show that the peptide discs, ~10 nm discoidal lipid bilayers stabilized in solution by a self-assembled 18A peptide belt, can be used as precursors for SLBs. The characterizations by means of neutron reflectometry and attenuated total reflectance-FTIR spectroscopy show that SLBs were successfully formed both from synthetic lipid mixtures (surface coverage 90-95%) and from natural lipid mixtures (surface coverage ~85%). Traces of 18A peptide (below 0.02 M ratio) left at the support surface after the bilayer formation do not affect the SLB structure. Altogether, we demonstrate that peptide disc formation of SLBs is much faster than the SLB formation by vesicle fusion and without the need of altering any experimental variable from physiologically relevant values.


Assuntos
Bicamadas Lipídicas , Peptídeos , Temperatura
10.
Biochim Biophys Acta Mol Cell Biol Lipids ; 1865(10): 158769, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32712249

RESUMO

Lipoproteins play a central role in the development of atherosclerosis. High and low-density lipoproteins (HDL and LDL), known as 'good' and 'bad' cholesterol, respectively, remove and/or deposit lipids into the artery wall. Hence, insight into lipid exchange processes between lipoproteins and cell membranes is of particular importance in understanding the onset and development of cardiovascular disease. In order to elucidate the impact of phospholipid tail saturation and the presence of cholesterol in cell membranes on these processes, neutron reflection was employed in the present investigation to follow lipid exchange with both HDL and LDL against model membranes. Mirroring clinical risk factors for the development of atherosclerosis, lower exchange was observed in the presence of cholesterol, as well as for an unsaturated phospholipid, compared to faster exchange when using a fully saturated phospholipid. These results highlight the importance of membrane composition on the interaction with lipoproteins, chiefly the saturation level of the lipids and presence of cholesterol, and provide novel insight into factors of importance for build-up and reversibility of atherosclerotic plaque. In addition, the correlation between the results and well-established clinical risk factors suggests that the approach taken can be employed also for understanding a broader set of risk factors including, e.g., effects of triglycerides and oxidative stress, as well as local effects of drugs on atherosclerotic plaque formation.


Assuntos
Aterosclerose/metabolismo , Colesterol/metabolismo , Lipídeos/genética , Lipoproteínas/genética , Aterosclerose/genética , Aterosclerose/patologia , Membrana Celular/genética , Membrana Celular/metabolismo , Colesterol/genética , Gorduras na Dieta , Ácidos Graxos , Humanos , Lipoproteínas/metabolismo , Lipoproteínas HDL/genética , Lipoproteínas HDL/metabolismo , Lipoproteínas LDL/genética , Lipoproteínas LDL/metabolismo , Fosfolipídeos/genética , Fosfolipídeos/metabolismo , Placa Aterosclerótica/metabolismo , Placa Aterosclerótica/patologia , Triglicerídeos/genética , Triglicerídeos/metabolismo
11.
Cancers (Basel) ; 12(7)2020 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-32605075

RESUMO

: Background obesity and sedentary lifestyle have been shown to negatively affect survival in breast cancer (BC). The purpose of this study was to test the efficacy of a lifestyle intervention on body mass index (BMI) and physical activity (PA) levels among BC survivors in Modena, Italy, in order to show an outcome improvement in obese and overweight patients. METHODS: This study is a single-arm experimental design, conducted between November 2009 and May 2016 on 430 women affected by BC. Weight, BMI, and PA were assessed at baseline, at 12 months, and at the end of the study. Survival curves were estimated among normal, overweight, and obese patients. RESULTS: Mean BMI decreased from baseline to the end of the study was equal to 2.9% (p = 0.065) in overweight patients and 3.3% in obese patients (p = 0.048). Mean PA increase from baseline to the end of the study was equal to 125% (p < 0.001) in normal patients, 200% (p < 0.001) in overweight patients and 100% (p < 0.001) in obese patients. After 70 months of follow-up, the 5-year overall survival (OS) rate was 96%, 96%, and 93%, respectively in normal, obese, and overweight patients. Overweight patients had significantly worse OS than normal ones (HR = 3.69, 95%CI = 1.82-4.53 p = 0.027) whereas no statistically significant differences were seen between obese and normal patients (HR 2.45, 95%CI = 0.68-8.78, p = 0.169). CONCLUSIONS: A lifestyle intervention can lead to clinically meaningful weight loss and increase PA in patients with BC. These results could contribute to improving the OS in obese patients compared to overweight ones.

12.
Adv Colloid Interface Sci ; 277: 102118, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32044469

RESUMO

Cellular membranes are complex structures and simplified analogues in the form of model membranes or biomembranes are used as platforms to understand fundamental properties of the membrane itself as well as interactions with various biomolecules such as drugs, peptides and proteins. Model membranes at the air-liquid and solid-liquid interfaces can be studied using a range of complementary surface-sensitive techniques to give a detailed picture of both the structure and physicochemical properties of the membrane and its resulting interactions. In this review, we will present the main planar model membranes used in the field to date with a focus on monolayers at the air-liquid interface, supported lipid bilayers at the solid-liquid interface and advanced membrane models such as tethered and floating membranes. We will then briefly present the principles as well as the main type of information on molecular interactions at model membranes accessible using a Langmuir trough, quartz crystal microbalance with dissipation monitoring, ellipsometry, atomic force microscopy, Brewster angle microscopy, Infrared spectroscopy, and neutron and X-ray reflectometry. A consistent example for following biomolecular interactions at model membranes is used across many of the techniques in terms of the well-studied antimicrobial peptide Melittin. The overall objective is to establish an understanding of the information accessible from each technique, their respective advantages and limitations, and their complementarity.


Assuntos
Peptídeos Catiônicos Antimicrobianos/química , Membrana Celular/química , Lipídeos/química , Peptídeos Catiônicos Antimicrobianos/metabolismo , Membrana Celular/metabolismo , Humanos , Bicamadas Lipídicas/química , Bicamadas Lipídicas/metabolismo , Modelos Moleculares , Propriedades de Superfície
13.
Cancer Med ; 9(7): 2579-2589, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32045136

RESUMO

BACKGROUND: Up to 10% of individuals with breast cancer (BC) belong to families with hereditary syndromes. The aim of this study was to develop an instrument to identify individuals/families at high-hereditary risk for BC and offer dedicated surveillance programs according to different risks. METHODS: The instrument consisted of a primary questionnaire collecting history of BC and ovarian cancer (OC). This questionnaire was applied to women enrolled in the Emilia-Romagna Breast Cancer Screening Program. General practitioners (GPs) and specialists could propose the same questionnaire too. Women with a score of ≥ 2, were invited to complete an oncogenetic counseling. According to the Tyrer-Cuzick evaluation, women considered at high risk were invited to involve the most representative alive individual of the family affected with BC/OC for BRCA1/2 genetic testing. RESULTS: Since January 2012 and December 2016, 660 040 women were evaluated by the regional screening program, of which 22 289 (3.5%) were invited to the Spoke evaluation, but only 5615 accepted (25.2%). Totally, also considering women sent by GPs and specialists, 11 667 were assessed and 5554 were sent to the Hub evaluation. Finally, 2342 (42.8%) women fulfilled the criteria for genetic testing, and 544 (23.2%) resulted BRCA1/2 mutation carriers. CONCLUSIONS: To our knowledge, this is the first regional population-based multistep model that is aimed to identify individuals with BRCA1/2 mutations and to offer an intensive surveillance program for hereditary-high risk women. This tool is feasible and effective, even if more efforts must be performed to increase the acceptance of multiple assessments by the study population.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/epidemiologia , Detecção Precoce de Câncer/métodos , Predisposição Genética para Doença , Testes Genéticos/métodos , Mutação , Adulto , Idoso , Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias da Mama/genética , Feminino , Seguimentos , Humanos , Itália/epidemiologia , Pessoa de Meia-Idade , Prognóstico
14.
Langmuir ; 34(6): 2312-2323, 2018 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-29323919

RESUMO

We demonstrate the ability to tune the formation of extended structures in films of poly(sodium styrenesulfonate)/dodecyltrimethylammonium bromide at the air/water interface through control over the charge/structure of aggregates as well as the ionic strength of the subphase. Our methodology to prepare loaded polyelectrolyte/surfactant films from self-assembled liquid crystalline aggregates exploits their fast dissociation and Marangoni spreading of material upon contact with an aqueous subphase. This process is proposed as a potential new route to prepare cheap biocompatible films for transfer applications. We show that films spread on water from swollen aggregates of low/negative charge have 1:1 charge binding and can be compressed only to a monolayer, beyond which material is lost to the bulk. For films spread on water from compact aggregates of positive charge, however, extended structures of the two components are created upon spreading or upon compression of the film beyond a monolayer. The application of ellipsometry, Brewster angle microscopy, and neutron reflectometry as well as measurements of surface pressure isotherms allow us to reason that formation of extended structures is activated by aggregates embedded in the film. The situation upon spreading on 0.1 M NaCl is different as there is a high concentration of small ions that stabilize loops of the polyelectrolyte upon film compression, yet extended structures of both components are only transient. Analogy of the controlled formation of extended structures in fluid monolayers is made to reservoir dynamics in lung surfactant. The work opens up the possibility to control such film dynamics in related systems through the rational design of particles in the future.

15.
Chem Phys Lipids ; 206: 60-70, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28648851

RESUMO

The increased biosynthesis of lysyl-phosphatidylglycerol in Staphylococcus aureus when cultured under conditions of mild acidity and the resultant increased proportion of this lipid in the plasma membrane of the bacterium, alters the physico-chemical properties of lipid bilayers in a manner which is itself dependent upon environmental pH. Clinically relevant strains of S. aureus, both methicillin susceptible and resistant, all exhibited increased lysyl-phosphatidylglycerol biosynthesis in response to mild environmental acidity, albeit to differing degrees, from ∼30% to ∼55% total phospholipid. Polar lipid extracts from these bacteria were analysed by 31P NMR and reconstituted into vesicles and monolayers, which were characterised by zeta potential measurements and Langmuir isotherms respectively. A combination of increased lysyl-phosphatidylglycerol content and mild environmental acidity were found to synergistically neutralise the charge of the membranes, in one instance altering the zeta potential from -56mV to +21mV, and induce closer packing between the lipids. Challenge of reconstituted S. aureus lipid model membranes by the antimicrobial peptide magainin 2 F5W was examined using monolayer subphase injection and neutron diffraction, and revealed that ionisation of the headgroup α-amine of lysyl-phosphatidylglycerol at pH 5.5, which reduced the magnitude of the peptide-lipid interaction by 80%, was more important for resisting peptide partitioning than increased lipid content alone. The significance of these results is discussed in relation to how colonising mildly acidic environments such as human mucosa may be facilitated by increased lysyl-phosphatidylglycerol biosynthesis and the implications of this for further biophysical analysis of the role of this lipid in bacterial membranes.


Assuntos
Membrana Celular/química , Fenômenos Químicos , Lisina/biossíntese , Staphylococcus aureus Resistente à Meticilina/citologia , Staphylococcus aureus Resistente à Meticilina/metabolismo , Fosfatidilgliceróis/biossíntese , Peptídeos Catiônicos Antimicrobianos/metabolismo , Peptídeos Catiônicos Antimicrobianos/farmacologia , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Fenômenos Químicos/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Lisina/metabolismo , Fluidez de Membrana/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Fosfatidilgliceróis/metabolismo , Pressão
16.
J Breast Cancer ; 19(3): 283-291, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27721878

RESUMO

PURPOSE: We conducted a study to evaluate the relationship between body mass index (BMI) and the risk of breast cancer (BC) and outcome in a population of 14,684 women aged 55 to 69 years eligible to participate in the Mammography Screening Program (MSP) in the Province of Modena, Italy. METHODS: The study population was drawn from women who underwent mammography screening between 2004 and 2006 in the Province of Modena. Women were subdivided into obese, overweight, and normal-weight categories according to BMI and followed until July 31, 2010, to evaluate the BC incidence. The clinicopathological characteristics of BC were also evaluated in different groups of patients classified according to BMI. After BC diagnosis, patients were followed for a median period of 65 (range, 2-104) months. Second events (recurrences and second tumors) were recorded, and the 5-year event-free survival (EFS) was calculated. RESULTS: After a period of 73 months, 366 cases of BC were diagnosed. Compared with normal-weight women, obese women had a significantly higher incidence of BC (relative risk [RR], 1.32; p=0.040) (RR=1), larger tumors (27% of tumors were larger than T2 size), and more nodal involvement (38.5% of tumors were node-positive). Furthermore, a significantly higher rate of total events was seen in obese women compared with overweight and normal-weight patients, respectively (17.9% vs. 11.4% vs. 10.8%, p=0.032). The 5-year EFS was 89.0%, 89.0%, and 80.0% for normal-weight, overweight, and obese patients, respectively. CONCLUSION: We observed a significantly higher risk of BC in obese women among those eligible to participate in the MSP in the Province of Modena. Finally, obese women had more second events and poorer EFS compared to nono bese women.

17.
Langmuir ; 31(50): 13535-42, 2015 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-26607026

RESUMO

It has been known for almost one hundred years that a lower surface tension can be achieved at the air-water interface by spreading protein from a concentrated solution than by adsorption from an equivalent total bulk concentration. Nevertheless, the factors that control this nonequilibrium process have not been fully understood. In the present work, we apply ellipsometry, neutron reflectometry, X-ray reflectometry, and Brewster angle microscopy to elaborate the surface loading of human serum albumin in terms of both the macroscopic film morphology and the spreading dynamics. We show that the dominant contribution to the surface loading mechanism is the Marangoni spreading of protein from the bulk of the droplets rather than the direct transfer of their surface films. The films can be spread on a dilute subphase if the concentration of the spreading solution is sufficient; if not, dissolution of the protein occurs, and only a textured adsorbed layer slowly forms. The morphology of the spread protein films comprises an extended network with regions of less textured material or gaps. Further, mechanical cycling of the surface area of the spread films anneals the network into a membrane that approach constant compressibility and has increased durability. Our work provides a new perspective on an old problem in colloid and interface science. The scope for optimization of the surface loading mechanism in a range of systems leading to its exploitation in deposition-based technologies in the future is discussed.


Assuntos
Ar , Albumina Sérica/química , Água/química , Humanos , Tamanho da Partícula , Propriedades de Superfície
18.
Int J Cancer ; 137(6): 1417-26, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-25736070

RESUMO

Although new treatments have been widely studied to improve the survival of patients with metastatic breast cancer (BC), prognosis continues to be poor with an average survival time no longer than 3 years. We carried on a population-based study with the purpose of evaluating the outcome of metastatic breast cancer in the province of Modena from 1990 to 2009. We examined the Modena Cancer Registry and evaluated the 5-year overall survival (OS) of women diagnosed with a de novo metastatic breast cancer between 1990 and 2009, defining 5 periods of 4 years each. After a median follow-up time of 29 months, the 5-year OS was 11% for years 1990-1993, 15% for years 1994-1997, 12% for years 1998-2001, 20% for years 2002-2005 and 29% for years 2006-2009 (p = 0.012). Overall, although no OS differences were noted in the first decade analyzed, a real advantage has been shown in the last two cohorts. In a multivariate analysis, the 5-year OS was significantly increased only for hormone receptor positive and HER2+ tumors, whereas chemotherapy treatments were not significant independent predictors of survival in "de novo" metastatic BC (p = 0.08). Our analysis confirms that the prognosis of de novo metastatic breast cancer has improved overtime, particularly in the last decade. Trastuzumab, LH-RH analogues and aromatase inhibitors have determined a significant clinical benefit and cost-effectiveness in metastatic breast cancer treatment.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Idoso , Anticorpos Monoclonais Humanizados/uso terapêutico , Inibidores da Aromatase/uso terapêutico , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Feminino , Hormônio Liberador de Gonadotropina/análogos & derivados , Humanos , Pessoa de Meia-Idade , Prognóstico , Receptor ErbB-2/metabolismo , Estudos Retrospectivos , Trastuzumab
19.
Phys Chem Chem Phys ; 16(26): 13220-8, 2014 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-24870051

RESUMO

Ozonolysis of methyl oleate monolayers at the air-water interface results in surprisingly rapid loss of material through cleavage of the C=C bond and evaporation/dissolution of reaction products. We determine using neutron reflectometry a rate coefficient of (5.7 ± 0.9) × 10(-10) cm(2) molecule(-1) s(-1) and an uptake coefficient of ∼3 × 10(-5) for the oxidation of a methyl ester monolayer: the atmospheric lifetime is ∼10 min. We obtained direct experimental evidence that <2% of organic material remains at the surface on atmospheric timescales. Therefore known long atmospheric residence times of unsaturated fatty acids suggest that these molecules cannot be present at the interface throughout their ageing cycle, i.e. the reported atmospheric longevity is likely to be attributed to presence in the bulk and viscosity-limited reactive loss. Possible reaction products were characterized by ellipsometry and uncertainties in the atmospheric fate of organic surfactants such as oleic acid and its methyl ester are discussed. Our results suggest that a minor change to the structure of the molecule (fatty acid vs. its methyl ester) considerably impacts on reactivity and fate of the organic film.


Assuntos
Ar , Atmosfera/química , Modelos Químicos , Ácidos Oleicos/química , Oxigênio/química , Ozônio/química , Água/química , Alcenos/química , Alcinos/química , Simulação por Computador , Cinética , Oxirredução , Propriedades de Superfície
20.
Eur J Cancer ; 49(18): 3881-8, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24011933

RESUMO

PURPOSE: We investigated the effect of fasting blood glucose and body mass index (BMI) at diagnosis on risk of breast cancer death for cases diagnosed in five Italian cancer registries in 2003-2005 and followed up to the end of 2008. METHODS: For 1607 Italian women (≥15 years) with information on BMI or blood glucose or diabetes, we analysed the risk of breast cancer death in relation to glucose tertiles (≤84.0, 84.1-94.0, >94.0 mg/dl) plus diabetic and unspecified categories; BMI tertiles (≤23.4, 23.5-27.3, >27.3 kg/m(2), unspecified), stage (T1-3N0M0, T1-3N+M0 plus T4anyNM0, M1, unspecified), oestrogen (ER) and progesterone (PR) status (ER+PR+, ER-PR-, ER and PR unspecified, other), age, chemotherapy and endocrine therapy, using multiple regression models. Separate models for ER+PR+ and ER-PR- cases were also run. RESULTS: Patients often had T1-3N0M0, ER+PR+ cancers and received chemotherapy or endocrine therapy; only 6% were M1 and 17% ER-PR-. Diabetic patients were older and had more often high BMI (>27 kg/m(2)), ER-PR-, M1 cancers than other patients. For ER+PR+ cases, with adjustment for other variables, breast cancer mortality was higher in women with high BMI than those with BMI 23.5-27.3 kg/m(2) (hazard ratio (HR)=2.9, 95% confidence interval (CI) 1.2-6.9). Breast cancer mortality was also higher in women with high (>94 mg/dl) blood glucose compared to those with glucose 84.1-94.0mg/dl (HR=2.6, 95% CI 1.2-5.7). CONCLUSION: Our results provide evidence that in ER+PR+ patients, high blood glucose and high BMI are independently associated with increased risk of breast cancer death. Detection and correction of these factors in such patients may improve prognosis.


Assuntos
Glicemia/metabolismo , Neoplasias da Mama/mortalidade , Jejum/sangue , Obesidade/complicações , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Neoplasias da Mama/complicações , Neoplasias da Mama/metabolismo , Complicações do Diabetes , Feminino , Humanos , Itália , Modelos Logísticos , Pessoa de Meia-Idade , Análise Multivariada , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Sistema de Registros/estatística & dados numéricos , Medição de Risco , Fatores de Risco , Taxa de Sobrevida , Adulto Jovem
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