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1.
Int J Mol Sci ; 25(4)2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38397013

RESUMO

Iron overload in many brain regions is a common feature of aging and most neurodegenerative diseases. In this review, the causes, mechanisms, mathematical models, and possible therapies are summarized. Indeed, physiological and pathological conditions can be investigated using compartmental models mimicking iron trafficking across the blood-brain barrier and the Cerebrospinal Fluid-Brain exchange membranes located in the choroid plexus. In silico models can investigate the alteration of iron homeostasis and simulate iron concentration in the brain environment, as well as the effects of intracerebral iron chelation, determining potential doses and timing to recover the physiological state. Novel formulations of non-toxic nanovectors with chelating capacity are already tested in organotypic brain models and could be available to move from in silico to in vivo experiments.


Assuntos
Sobrecarga de Ferro , Doenças Neurodegenerativas , Humanos , Encéfalo , Barreira Hematoencefálica/fisiologia , Ferro , Sobrecarga de Ferro/tratamento farmacológico , Doenças Neurodegenerativas/tratamento farmacológico
2.
Int J Mol Sci ; 25(2)2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38255803

RESUMO

Excessive iron levels are believed to contribute to the development of neurodegenerative disorders by promoting oxidative stress and harmful protein clustering. Novel chelation treatments that can effectively remove excess iron while minimizing negative effects on the nervous system are being explored. This study focuses on the creation and evaluation of innovative nanobubble (NB) formulations, shelled with various polymers such as glycol-chitosan (GC) and glycol-chitosan conjugated with deferoxamine (DFO), to enhance their ability to bind iron. Various methods were used to evaluate their physical and chemical properties, chelation capacity in diverse iron solutions and impact on reactive oxygen species (ROS). Notably, the GC-DFO NBs demonstrated the ability to decrease amyloid-ß protein misfolding caused by iron. To assess potential toxicity, in vitro cytotoxicity testing was conducted using organotypic brain cultures from the substantia nigra, revealing no adverse effects at appropriate concentrations. Additionally, the impact of NBs on spontaneous electrical signaling in hippocampal neurons was examined. Our findings suggest a novel nanochelation approach utilizing DFO-conjugated NBs for the removal of excess iron in cerebral regions, potentially preventing neurotoxic effects.


Assuntos
Sobrecarga de Ferro , Ferro , Humanos , Sistema Nervoso Central , Encéfalo , Peptídeos beta-Amiloides
3.
Int J Mol Sci ; 24(21)2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37958582

RESUMO

In both healthcare and agriculture, antibiotic resistance is an alarming issue. Biocompatible and biodegradable ingredients (e.g., curcumin) are given priority in "green" criteria supported by the Next Generation EU platform. The solubility and stability of curcumin would be significantly improved if it were enclosed in nanobubbles (NB), and photoactivation with the correct wavelength of light can increase its antibacterial efficacy. A continuous release of curcumin over a prolonged period was provided by using innovative chitosan-shelled carriers, i.e., curcumin-containing nanobubbles (Curc-CS-NBs) and oxygen-loaded curcumin-containing nanobubbles (Curc-Oxy-CS-NBs). The results demonstrated that after photoactivation, both types of NBs exhibited increased effectiveness. For Staphylococcus aureus, the minimum inhibitory concentration (MIC) for Curc-CS-NBs remained at 46 µg/mL following photodynamic activation, whereas it drastically dropped to 12 µg/mL for Curc-Oxy-CS-NBs. Enterococcus faecalis shows a decreased MIC for Curc-CS-NB and Curc-Oxy-CS-NB (23 and 46 µg/mL, respectively). All bacterial strains were more effectively killed by NBs that had both oxygen and LED irradiation. A combination of Curc-Oxy-CS-NB and photodynamic stimulation led to a killing of microorganisms due to ROS-induced bacterial membrane leakage. This approach was particularly effective against Escherichia coli. In conclusion, this work shows that Curc-CS-NBs and Curc-Oxy-CS-exhibit extremely powerful antibacterial properties and represent a potential strategy to prevent antibiotic resistance and encourage the use of eco-friendly substitutes in agriculture and healthcare.


Assuntos
Anti-Infecciosos , Quitosana , Curcumina , Curcumina/farmacologia , Anti-Infecciosos/farmacologia , Antibacterianos/farmacologia , Quitosana/farmacologia , Solubilidade
4.
Molecules ; 28(21)2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37959823

RESUMO

Iron, a crucial element in our environment, plays a vital role in numerous natural processes. Understanding the presence and concentration of iron in the environment is very important as it impacts various aspects of our planet's health. The on-site detection and speciation of iron are significant for several reasons. In this context, the present work aims to evaluate the applicability of voltammetry for the on-site determination of iron and its possible speciation using a portable voltammetric analyzer. Voltammetry offers the advantage of convenience and cost-effectiveness. For iron (III) determination, the modification of a glassy carbon electrode (GCE) with an antimony-bismuth film (SbBiFE) using the acetate buffer (pH = 4) as a supporting electrolyte was used. The technique adopted was Square Wave Adsoptive Cathodic Stripping Voltammetry (SW-AdCSV), and we used 1-(2-piridylazo)-2-naphthol (PAN) as the iron (III) ligand. Linearity, repeatability, detection limit, and accuracy were determined using synthetic solutions; then, a Standard Reference Material (SRM) of 1643f Trace Elements in Water (iron content: 93.44 ± 0.78 µg L-1) was used for validation measurements in the real matrix. the accuracy of this technique was found to be excellent since we obtained a recovery of 103.16%. The procedure was finally applied to real samples (tap, lake, and seawater), and the results obtained were compared via Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES). The amount of iron found was 207.8 ± 6.6 µg L-1 for tap water using voltammetry and 200.9 ± 1.5 µg L-1 with ICP-OES. For lake water, 171.7 ± 3.8 µg L-1, 169.8 ± 4.1 µg L-1, and 187.5 ± 5.7 µg L-1 were found using voltammetry in the lab both on-site and using ICP-OES, respectively. The results obtained demonstrate the excellent applicability of the proposed on-site voltammetric procedure for the determination of iron and its speciation in water.

5.
Int J Mol Sci ; 23(17)2022 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-36077413

RESUMO

The alteration of iron homeostasis related to the aging process is responsible for increased iron levels, potentially leading to oxidative cellular damage. Iron is modulated in the Central Nervous System in a very sensitive manner and an abnormal accumulation of iron in the brain has been proposed as a biomarker of neurodegeneration. However, contrasting results have been presented regarding brain iron accumulation and the potential link with other factors during aging and neurodegeneration. Such uncertainties partly depend on the fact that different techniques can be used to estimate the distribution of iron in the brain, e.g., indirect (e.g., MRI) or direct (post-mortem estimation) approaches. Furthermore, recent evidence suggests that the propensity of brain cells to accumulate excessive iron as a function of aging largely depends on their anatomical location. This review aims to collect the available data on the association between iron concentration in the brain and aging, shedding light on potential mechanisms that may be helpful in the detection of physiological neurodegeneration processes and neurodegenerative diseases such as Alzheimer's disease.


Assuntos
Encéfalo , Doenças Neurodegenerativas , Humanos , Ferro , Quelantes de Ferro
6.
Int J Mol Sci ; 23(5)2022 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-35269742

RESUMO

In the search for non-chemical and green methods to counteract the bacterial contamination of foods, the use of natural substances with antimicrobial properties and light irradiation at proper light waves has been extensively investigated. In particular, the combination of both techniques, called photodynamic inactivation (PDI), is based on the fact that some natural substances act as photosensitizers, i.e., produce bioactive effects under irradiation. Notably, curcumin is a potent natural antibacterial and effective photosensitizer that is able to induce photodynamic activation in the visible light range (specifically for blue light). Some practical applications have been investigated with particular reference to food preservation from bacterial contaminants.


Assuntos
Curcumina , Fotoquimioterapia , Antibacterianos/farmacologia , Bactérias , Curcumina/farmacologia , Conservação de Alimentos/métodos , Luz , Fármacos Fotossensibilizantes/farmacologia
7.
Int J Mol Sci ; 22(9)2021 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-33923052

RESUMO

Proper functioning of all organs, including the brain, requires iron. It is present in different forms in biological fluids, and alterations in its distribution can induce oxidative stress and neurodegeneration. However, the clinical parameters normally used for monitoring iron concentration in biological fluids (i.e., serum and cerebrospinal fluid) can hardly detect the quantity of circulating iron, while indirect measurements, e.g., magnetic resonance imaging, require further validation. This review summarizes the mechanisms involved in brain iron metabolism, homeostasis, and iron imbalance caused by alterations detectable by standard and non-standard indicators of iron status. These indicators for iron transport, storage, and metabolism can help to understand which biomarkers can better detect iron imbalances responsible for neurodegenerative diseases.


Assuntos
Doença de Alzheimer/diagnóstico , Biomarcadores/sangue , Encéfalo/metabolismo , Ferroptose/fisiologia , Ferro/metabolismo , Doença de Alzheimer/metabolismo , Biomarcadores/líquido cefalorraquidiano , Encéfalo/patologia , Ceruloplasmina/deficiência , Ceruloplasmina/metabolismo , Ferritinas/sangue , Ferritinas/líquido cefalorraquidiano , Ferritinas/metabolismo , Humanos , Ferro/sangue , Ferro/líquido cefalorraquidiano , Distúrbios do Metabolismo do Ferro/metabolismo , Imageamento por Ressonância Magnética , Doenças Neurodegenerativas/metabolismo , Estresse Oxidativo/fisiologia , Transferrina/líquido cefalorraquidiano , Transferrina/metabolismo
8.
Molecules ; 26(15)2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34361743

RESUMO

While investigating the possible synergistic effect of the conventional anticancer therapies, which, taken individually, are often ineffective against critical tumors, such as central nervous system (CNS) ones, the design of a theranostic nanovector able to carry and deliver chemotherapy drugs and magnetic hyperthermic agents to the target radiosensitizers (oxygen) was pursued. Alongside the original formulation of polymeric biodegradable oxygen-loaded nanostructures, their properties were fine-tuned to optimize their ability to conjugate therapeutic doses of drugs (doxorubicin) or antitumoral natural substances (curcumin). Oxygen-loaded nanostructures (diameter = 251 ± 13 nm, ζ potential = -29 ± 5 mV) were finally decorated with superparamagnetic iron oxide nanoparticles (SPIONs, diameter = 18 ± 3 nm, ζ potential = 14 ± 4 mV), producing stable, effective and non-agglomerating magnetic nanovectors (diameter = 279 ± 17 nm, ζ potential = -18 ± 7 mV), which could potentially target the tumoral tissues under magnetic driving and are monitorable either by US or MRI imaging.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Quitosana/química , Hipertermia Induzida/métodos , Nanopartículas de Magnetita/química , Radiossensibilizantes/farmacologia , Nanomedicina Teranóstica/métodos , Antibióticos Antineoplásicos/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Meios de Contraste/síntese química , Meios de Contraste/farmacologia , Curcumina/química , Curcumina/farmacologia , Sulfato de Dextrana/química , Doxorrubicina/química , Doxorrubicina/farmacologia , Composição de Medicamentos/métodos , Humanos , Cinética , Nanopartículas de Magnetita/ultraestrutura , Oxigênio/química , Oxigênio/farmacologia , Radiossensibilizantes/síntese química
9.
Mol Imaging ; 17: 1536012118778216, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30213222

RESUMO

Ultrasound Contrast Agents (UCAs) consisting of gas-filled-coated Microbubbles (MBs) with diameters between 1 and 10 µm have been used for a number of decades in diagnostic imaging. In recent years, submicron contrast agents have proven to be a viable alternative to MBs for ultrasound (US)-based applications for their capability to extravasate and accumulate in the tumor tissue via the enhanced permeability and retention effect. After a short overview of the more recent approaches to ultrasound-mediated imaging and therapeutics at the nanoscale, phase-change contrast agents (PCCAs), which can be phase-transitioned into highly echogenic MBs by means of US, are here presented. The phenomenon of acoustic droplet vaporization (ADV) to produce bubbles is widely investigated for both imaging and therapeutic applications to develop promising theranostic platforms.


Assuntos
Nanotecnologia , Nanomedicina Teranóstica , Ultrassonografia , Acústica , Humanos , Microbolhas , Volatilização
10.
Pharm Res ; 35(4): 75, 2018 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-29484487

RESUMO

PURPOSE: Chitosan-shelled/decafluoropentane-cored oxygen-loaded nanodroplets (OLN) are a new class of nanodevices to effectively deliver anti-cancer drugs to tumoral cells. This study investigated their antitumoral effects 'per se', using a mathematical model validated on experimental data. METHODS: OLN were prepared and characterized either in vitro or in vivo. TUBO cells, established from a lobular carcinoma of a BALB-neuT mouse, were investigated following 48 h of incubation in the absence/presence of different concentrations of OLN. OLN internalization, cell viability, necrosis, apoptosis, cell cycle and reactive oxygen species (ROS) production were checked as described in the Method section. In vivo tumor growth was evaluated after subcutaneous transplant in BALB/c mice of TUBO cells either without treatment or after 24 h incubation with 10% v/v OLN. RESULTS: OLN showed sizes of about 350 nm and a positive surface charge (45 mV). Dose-dependent TUBO cell death through ROS-triggered apoptosis following OLN internalization was detected. A mathematical model predicting the effects of OLN uptake was validated on both in vitro and in vivo results. CONCLUSIONS: Due to their intrinsic toxicity OLN might be considered an adjuvant tool suitable to deliver their therapeutic cargo intracellularly and may be proposed as promising combined delivery system.


Assuntos
Antineoplásicos/administração & dosagem , Composição de Medicamentos/métodos , Sistemas de Liberação de Medicamentos/métodos , Nanopartículas/química , Animais , Carcinoma de Mama in situ/tratamento farmacológico , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral/transplante , Sobrevivência Celular/efeitos dos fármacos , Quitosana/química , Simulação por Computador , Modelos Animais de Doenças , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Fluorocarbonos/química , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Modelos Biológicos , Oxigênio/química
11.
Molecules ; 23(1)2017 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-29267188

RESUMO

One of the most challenging goals in pharmacological research is overcoming the Blood Brain Barrier (BBB) to deliver drugs to the Central Nervous System (CNS). The use of physical means, such as steady and alternating magnetic fields to drive nanocarriers with proper magnetic characteristics may prove to be a useful strategy. The present review aims at providing an up-to-date picture of the applications of magnetic-driven nanotheranostics agents to the CNS. Although well consolidated on physical ground, some of the techniques described herein are still under investigation on in vitro or in silico models, while others have already entered in-or are close to-clinical validation. The review provides a concise overview of the physical principles underlying the behavior of magnetic nanoparticles (MNPs) interacting with an external magnetic field. Thereafter we describe the physiological pathways by which a substance can reach the brain from the bloodstream and then we focus on those MNP applications that aim at a nondestructive crossing of the BBB such as static magnetic fields to facilitate the passage of drugs and alternating magnetic fields to increment BBB permeability by magnetic heating. In conclusion, we briefly cite the most notable biomedical applications of MNPs and some relevant remarks about their safety and potential toxicity.


Assuntos
Sistema Nervoso Central/efeitos dos fármacos , Nanopartículas de Magnetita/efeitos adversos , Nanopartículas de Magnetita/química , Animais , Transporte Biológico , Barreira Hematoencefálica/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Humanos , Campos Magnéticos , Modelos Biológicos , Tamanho da Partícula , Permeabilidade , Propriedades de Superfície
12.
Biosci Biotechnol Biochem ; 80(3): 466-72, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26523859

RESUMO

Matrix metalloproteinases (MMPs) and their endogenous inhibitors (TIMPs) need to be finely modulated in physiological processes. However, oxygen tension influences MMP/TIMP balances, potentially leading to pathology. Intriguingly, new 2H,3H-decafluoropentane-based oxygen-loaded nanodroplets (OLNDs) have proven effective in abrogating hypoxia-dependent dysregulation of MMP and TIMP secretion by single cell populations. This work explored the effects of different oxygen tensions and dextran-shelled OLNDs on MMP/TIMP production in an organized and multicellular tissue (term human placenta). Chorionic villous explants from normal third-trimester pregnancies were incubated with/without OLNDs in 3 or 20% O2. Explants cultured at higher oxygen tension released constitutive proMMP-2, proMMP-9, TIMP-1, and TIMP-2. Hypoxia significantly altered MMP-2/TIMP-2 and MMP-9/TIMP-1 ratios enhancing TIMP-2 and reducing proMMP-2, proMMP-9, and TIMP-1 levels. Intriguingly, OLNDs effectively counteracted the effects of low oxygen tension. Collectively, these data support OLND potential as innovative, nonconventional, and cost-effective tools to counteract hypoxia-dependent dysregulation of MMP/TIMP balances in human tissues.


Assuntos
Dextranos/química , Inibidores Enzimáticos/metabolismo , Fluorocarbonos/química , Gelatinases/metabolismo , Nanoestruturas , Oxigênio/química , Placenta/enzimologia , Inibidores Enzimáticos/farmacologia , Feminino , Gelatinases/antagonistas & inibidores , Humanos , Placenta/metabolismo , Gravidez
13.
Toxicol Appl Pharmacol ; 286(3): 198-206, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-25937238

RESUMO

BACKGROUND: In chronic wounds, efficient epithelial tissue repair is hampered by hypoxia, and balances between the molecules involved in matrix turn-over such as matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) are seriously impaired. Intriguingly, new oxygenating nanocarriers such as 2H,3H-decafluoropentane-based oxygen-loaded nanodroplets (OLNs) might effectively target chronic wounds. OBJECTIVE: To investigate hypoxia and chitosan-shelled OLN effects on MMP/TIMP production by human keratinocytes. METHODS: HaCaT cells were treated for 24h with 10% v/v OLNs both in normoxia or hypoxia. Cytotoxicity and cell viability were measured through biochemical assays; cellular uptake by confocal microscopy; and MMP and TIMP production by enzyme-linked immunosorbent assay or gelatin zymography. RESULTS: Normoxic HaCaT cells constitutively released MMP-2, MMP-9, TIMP-1 and TIMP-2. Hypoxia strongly impaired MMP/TIMP balances by reducing MMP-2, MMP-9, and TIMP-2, without affecting TIMP-1 release. After cellular uptake by keratinocytes, nontoxic OLNs abrogated all hypoxia effects on MMP/TIMP secretion, restoring physiological balances. OLN abilities were specifically dependent on time-sustained oxygen diffusion from OLN core. CONCLUSION: Chitosan-shelled OLNs effectively counteract hypoxia-dependent dysregulation of MMP/TIMP balances in human keratinocytes. Therefore, topical administration of exogenous oxygen, properly encapsulated in nanodroplet formulations, might be a promising adjuvant approach to promote healing processes in hypoxic wounds.


Assuntos
Quitosana/administração & dosagem , Gelatinases/antagonistas & inibidores , Queratinócitos/efeitos dos fármacos , Nanopartículas/administração & dosagem , Oxigênio/administração & dosagem , Cicatrização/efeitos dos fármacos , Hipóxia Celular/efeitos dos fármacos , Hipóxia Celular/fisiologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Quitosana/química , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/química , Inibidores Enzimáticos/farmacologia , Gelatinases/metabolismo , Humanos , Queratinócitos/enzimologia , Masculino , Pessoa de Meia-Idade , Nanopartículas/química , Oxigênio/química , Cicatrização/fisiologia
14.
Toxicol Appl Pharmacol ; 288(3): 330-8, 2015 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-26276311

RESUMO

In chronic wounds, hypoxia seriously undermines tissue repair processes by altering the balances between pro-angiogenic proteolytic enzymes (matrix metalloproteinases, MMPs) and their inhibitors (tissue inhibitors of metalloproteinases, TIMPs) released from surrounding cells. Recently, we have shown that in human monocytes hypoxia reduces MMP-9 and increases TIMP-1 without affecting TIMP-2 secretion, whereas in human keratinocytes it reduces MMP-2, MMP-9, and TIMP-2, without affecting TIMP-1 release. Provided that the phenotype of the cellular environment is better understood, chronic wounds might be targeted by new oxygenating compounds such as chitosan- or dextran-shelled and 2H,3H-decafluoropentane-cored oxygen-loaded nanodroplets (OLNs). Here, we investigated the effects of hypoxia and dextran-shelled OLNs on the pro-angiogenic phenotype and behavior of human dermal microvascular endothelium (HMEC-1 cell line), another cell population playing key roles during wound healing. Normoxic HMEC-1 constitutively released MMP-2, TIMP-1 and TIMP-2 proteins, but not MMP-9. Hypoxia enhanced MMP-2 and reduced TIMP-1 secretion, without affecting TIMP-2 levels, and compromised cell ability to migrate and invade the extracellular matrix. When taken up by HMEC-1, nontoxic OLNs abrogated the effects of hypoxia, restoring normoxic MMP/TIMP levels and promoting cell migration, matrix invasion, and formation of microvessels. These effects were specifically dependent on time-sustained oxygen diffusion from OLN core, since they were not achieved by oxygen-free nanodroplets or oxygen-saturated solution. Collectively, these data provide new information on the effects of hypoxia on dermal endothelium and support the hypothesis that OLNs might be used as effective adjuvant tools to promote chronic wound healing processes.


Assuntos
Indutores da Angiogênese/farmacologia , Dextranos/farmacologia , Endotélio Vascular/efeitos dos fármacos , Hipóxia/tratamento farmacológico , Nanoestruturas/química , Oxigênio/farmacologia , Indutores da Angiogênese/química , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Quitosana/química , Quitosana/farmacologia , Dextranos/química , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/metabolismo , Gelatinases/metabolismo , Humanos , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Oxigênio/química , Fenótipo , Pele/efeitos dos fármacos , Pele/metabolismo , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Inibidor Tecidual de Metaloproteinase-2/metabolismo , Cicatrização/efeitos dos fármacos
15.
Mediators Inflamm ; 2015: 964838, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25878404

RESUMO

Monocytes play a key role in the inflammatory stage of the healing process. To allow monocyte migration to injured tissues, the balances between secreted matrix metalloproteinases (MMPs) and their inhibitors (TIMPs) must be finely modulated. However, a reduction of blood supply and local oxygen tension can modify the phenotype of immune cells. Intriguingly, hypoxia might be targeted by new effective oxygenating devices such as 2H,3H-decafluoropentane- (DFP-) based oxygen-loaded nanodroplets (OLNs). Here, hypoxia effects on gelatinase/TIMP release from human peripheral monocytes were investigated, and the therapeutic potential of dextran-shelled OLNs was evaluated. Normoxic monocytes constitutively released ~500 ng/mL MMP-9, ~1.3 ng/mL TIMP-1, and ~0.6 ng/mL TIMP-2 proteins. MMP-2 was not detected. After 24 hours, hypoxia significantly altered MMP-9/TIMP-1 balance by reducing MMP-9 and increasing TIMP-1, without affecting TIMP-2 secretion. Interestingly OLNs, not displaying toxicity to human monocytes after cell internalization, effectively counteracted hypoxia, restoring a normoxia-like MMP-9/TIMP-1 ratio. The action of OLNs was specifically dependent on time-sustained oxygen diffusion up to 24 h from their DFP-based core. Therefore, OLNs appear as innovative, nonconventional, cost-effective, and nontoxic therapeutic tools, to be potentially employed to restore the physiological invasive phenotype of immune cells in hypoxia-associated inflammation.


Assuntos
Hipóxia/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Monócitos/metabolismo , Nanopartículas/administração & dosagem , Oxigênio/administração & dosagem , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Humanos
16.
Theor Biol Med Model ; 11: 44, 2014 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-25312098

RESUMO

BACKGROUND: Children receiving Total Body Irradiation (TBI) in preparation for Hematopoietic Stem Cell Transplantation (HSCT) are at risk for Growth Hormone Deficiency (GHD), which sometimes severely compromises their Final Height (FH). To better represent the impact of such therapies on growth we apply a mathematical model, which accounts both for the gompertzian-like growth trend and the hormone-related 'spurts', and evaluate how the parameter values estimated on the children undergoing TBI differ from those of the matched normal population. METHODS: 25 patients long-term childhood lymphoblastic and myeloid acute leukaemia survivors followed at Pediatric Onco-Hematology, Stem Cell Transplantation and Cellular Therapy Division, Regina Margherita Children's Hospital (Turin, Italy) were retrospectively analysed for assessing the influence of TBI on their longitudinal growth and for validating a new method to estimate the GH therapy effects. Six were treated with GH therapy after a GHD diagnosis. RESULTS: We show that when TBI was performed before puberty overall growth and pubertal duration were significantly impaired, but such growth limitations were completely reverted in the small sample (6 over 25) of children who underwent GH replacement therapies. CONCLUSION: Since in principle the model could account for any additional growth 'spurt' induced by therapy, it may become a useful 'simulation' tool for paediatricians for comparing the predicted therapy effectiveness depending on its timing and dosage.


Assuntos
Crescimento/efeitos da radiação , Leucemia/cirurgia , Irradiação Corporal Total , Adolescente , Criança , Feminino , Transplante de Células-Tronco Hematopoéticas , Humanos , Lactente , Leucemia/radioterapia , Masculino , Estudos Retrospectivos , Condicionamento Pré-Transplante
17.
Foods ; 12(10)2023 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-37238856

RESUMO

Background: According to recent studies, tens of millions of tons of fruit are wasted each year in Europe in primary production and home/service consumption. Among fruits, berries are most critical because they have a shorter shelf life and a softer, more delicate, and often edible skin. Curcumin is a natural polyphenolic compound extracted from the spice turmeric (Curcuma longa L.) which exhibits antioxidant, photophysical, and antimicrobial properties that can be further enhanced by photodynamic inactivation of pathogens when irradiated with blue or ultraviolet light. Materials and methods: Multiple experiments were performed in which berry samples were sprayed with a complex of ß-cyclodextrin containing 0.5 or 1 mg/mL of curcumin. Photodynamic inactivation was induced by irradiation with blue LED light. Antimicrobial effectiveness was assessed with microbiological assays. The expected effects of oxidation, curcumin solution deterioration, and alteration of the volatile compounds were investigated as well. Results: The treatment with photoactivated curcumin solutions reduced the bacterial load (3.1 vs. 2.5 colony forming units/mL (UFC/ml) in the control and treated groups; p-value = 0.01), without altering the fruit organoleptic and antioxidant properties. Conclusions: The explored method is a promising approach to extend berries' shelf life in an easy and green way. However, further investigations of the preservation and general properties of treated berries are still needed.

18.
Theor Biol Med Model ; 9: 17, 2012 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-22594680

RESUMO

OBJECTIVES: Several formulations have been proposed in order to model human growth from birth to maturity. They are usually based on "ad hoc" heuristic assumptions. In the present contribution we adopt, as an alternative, a completely general (interdisciplinary) approach, based on the formalism of the Phenomenological Universalities (PUN). METHODS: The main PUN class investigated to date, i.e. UN, can only account for the overall growth pattern. For a realistic description it is necessary to add to it one or more "spurts", as expected on biological grounds, due to the stimulation of growth and sex hormones. RESULTS: A new PUN class (UN + FM) is generated and shown to be able to provide excellent agreement with standard auxological datasets. The accuracy of the fitting and reliability of the model suggest applications both at the diagnostic and therapeutic level. CONCLUSIONS: The developed formalism can be suitably related to the biological description of bone plate growth under selective hormonal stimulation on the bone epiphysis; i.e., the additional increase of stature is the "macroscopic" response to a well defined biological signal.


Assuntos
Crescimento e Desenvolvimento , Modelos Biológicos , Adolescente , Envelhecimento/fisiologia , Estatura/fisiologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Síndrome de Noonan/fisiopatologia , Reino Unido , Adulto Jovem
19.
J Clin Ultrasound ; 40(3): 167-73, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22359401

RESUMO

Periodic quality control (QC) for ultrasound scanners checks their overall performance, reducing the risk of inaccurate diagnoses. Data from routine annual QC activity were analyzed to optimize the scheduling and the criteria of further QC programs. Among all the ultrasound scanners (68 transducers) in use at the Regional Medical Department of the Aosta Valley, which are currently tested, 48.6% showed problems, mainly (35.3%) related to defects detectable by physical and mechanical inspection. Nearly two-thirds of these problems impacted QC parameters. Failures were significantly related to the workload and to the "technological level" of the equipment. QC scheduling should therefore include a daily/weekly physical inspection in addition to a more complete, objective and software algorithms-based test, the frequency of which should be tailored on the basis of the equipment characteristics. © 2012 Wiley Periodicals, Inc. J Clin Ultrasound, 2012.


Assuntos
Ultrassonografia/instrumentação , Ultrassonografia/normas , Desenho de Equipamento , Controle de Qualidade , Ultrassonografia Doppler/instrumentação , Ultrassonografia Doppler/normas
20.
Tomography ; 8(4): 2093-2106, 2022 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-36006074

RESUMO

Previous studies demonstrated sex-related differences in several areas of the human brain, including patterns of brain activation in males and females when observing their own bodies and faces (versus other bodies/faces or morphed versions of themselves), but a complex paradigm touching multiple aspects of embodied self-identity is still lacking. We enrolled 24 healthy individuals (12 M, 12 F) in 3 different fMRI experiments: the vision of prototypical body silhouettes, the vision of static images of the face of the participants morphed with prototypical male and female faces, the vision of short videos showing the dynamic transformation of the morphing. We found differential sexual activations in areas linked to self-identity and to the ability to attribute mental states: In Experiment 1, the male group activated more the bilateral thalamus when looking at sex congruent body images, while the female group activated more the middle and inferior temporal gyrus. In Experiment 2, the male group activated more the supplementary motor area when looking at their faces; the female group activated more the dorsomedial prefrontal cortex (dmPFC). In Experiment 3, the female group activated more the dmPFC when observing either the feminization or the masculinization of their face. The defeminization produced more activations in females in the left superior parietal lobule and middle occipital gyrus. The performance of all classifiers built using single ROIs exceeded chance level, reaching an area under the ROC curves > 0.85 in some cases (notably, for Experiment 2 using the V1 ROI). The results of the fMRI tasks showed good agreement with previously published studies, even if our sample size was small. Therefore, our functional MRI protocol showed significantly different patterns of activation in males and females, but further research is needed both to investigate the gender-related differences in activation when observing a morphing of their face/body, and to validate our paradigm using a larger sample.


Assuntos
Mapeamento Encefálico , Feminização , Imagem Corporal , Encéfalo/diagnóstico por imagem , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino
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