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1.
Analyst ; 144(2): 488-497, 2019 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-30467573

RESUMO

The present work aims to study the effects that acute exposure to low concentrations of silver nanoparticles (AgNPs) cause in digestive glands of terrestrial isopods (Porcellio scaber). The experiments were designed to integrate different analytical techniques, such as transmission electron microscopy, atomic absorption spectroscopy, proton induced X-ray emission, and Fourier transform IR imaging (FTIRI), in order to gain a comprehensive insight into the process from the AgNPs' synthesis to their interaction with biological tissues in vivo. To this aim, terrestrial isopods were fed with AgNPs having different shapes, sizes, and concentrations. For all the tested conditions, no toxicity at the whole organism level was observed after 14 days of exposure. However, FTIRI showed that AgNPs caused detectable local changes in proteins, lipids, nucleic acids and carbohydrates at the tissue level, to an extent dependent on the interplay of the AgNPs' properties: shape, size, concentration and dissolution of ions from them.


Assuntos
Isópodes/química , Nanopartículas Metálicas/química , Prata/química , Animais , Feminino , Mucosa Intestinal/química , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Isópodes/efeitos dos fármacos , Isópodes/metabolismo , Masculino , Nanopartículas Metálicas/administração & dosagem , Microscopia , Tamanho da Partícula , Análise de Componente Principal , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier
2.
Analyst ; 138(14): 4015-21, 2013 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-23662303

RESUMO

The knowledge of cell cycle phase distribution is of paramount importance for understanding cellular behaviour under normal and stressed growth conditions. This task is usually assessed using Flow Cytometry (FC) or immunohistochemistry. Here we report on the use of FTIR microspectroscopy in Microfluidic Devices (MD-IRMS) as an alternative technique for studying cell cycle distribution in live cells. Asynchronous, S- and G0-synchronized B16 mouse melanoma cells were studied by running parallel experiments based on MD-IRMS and FC using Propidium Iodide (PI) staining. MD-IRMS experiments have been done using silicon-modified BaF2 devices, where the thin silicon layer prevents BaF2 dissolution without affecting the transparency of the material and therefore enabling a better assessment of the Phosphate I (PhI) and II (PhII) bands. Hierarchical Cluster Analysis (HCA) of cellular microspectra in the 1300-1000 cm(-1) region pointed out a distribution of cells among clusters, which is in good agreement with FC results among G0/G1, S and G2/M phases. The differentiation is mostly driven by the intensity of PhI and PhII bands. In particular, PhI almost doubles from the G0/G1 to G2/M phase, in agreement with the trend followed by nucleic acids during cellular progression. MD-IRMS is then proposed as a powerful method for the in situ determination of the cell cycle stage of an individual cell, without any labelling or staining, which gives the advantage of possibly monitoring specific cellular responses to several types of stimuli by clearly separating the spectral signatures related to the cellular response from those of cells that are normally progressing.


Assuntos
Ciclo Celular/fisiologia , Fenômenos Fisiológicos Celulares , Melanoma Experimental/patologia , Técnicas Analíticas Microfluídicas/instrumentação , Ácidos Nucleicos/análise , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Animais , Análise por Conglomerados , Citometria de Fluxo , Melanoma Experimental/genética , Camundongos , Propídio , Células Tumorais Cultivadas
3.
Environ Sci Technol ; 47(19): 11284-92, 2013 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-23952740

RESUMO

Tungsten nanofibers are recognized as biologically potent. We study deviations in molecular composition between normal and digestive gland tissue of WOx nanofibers (nano-WOx) fed invertebrate Porcellio scaber (Iosopda, Crustacea) and revealed mechanisms of nano-WOx effect in vivo. Fourier Transform Infrared (FTIR) imaging performed on digestive gland epithelium was supplemented by toxicity and cytotoxicity analyses as well as scanning electron microscopy (SEM) of the surface of the epithelium. The difference in the spectra of the Nano-WOx treated and control cells showed up in the central region of the cells and were related to lipid peroxidation, and structural changes of nucleic acids. The conventional toxicity parameters failed to show toxic effects of nano-WOx, whereas the cytotoxicity biomarkers and SEM investigation of digestive gland epithelium indicated sporadic effects of nanofibers. Since toxicological and cytological measurements did not highlight severe effects, the biochemical alterations evidenced by FTIR imaging have been explained as the result of cell protection (acclimation) mechanisms to unfavorable conditions and indication of a nonhomeostatic state, which can lead to toxic effects.


Assuntos
Sistema Digestório/efeitos dos fármacos , Nanofibras/toxicidade , Óxidos/toxicidade , Tungstênio/toxicidade , Animais , Membrana Celular/efeitos dos fármacos , Sistema Digestório/citologia , Comportamento Alimentar/efeitos dos fármacos , Isópodes , Espectroscopia de Infravermelho com Transformada de Fourier
4.
Reprod Fertil Dev ; 24(6): 794-803, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22781930

RESUMO

This study aimed to investigate the effects of two different doses (100nM (M1) and 1µM (M2)) of exogenous melatonin on the reproductive capacity of Fundulus heteroclitus. Eight days of melatonin exposure significantly increased the fecundity and embryo survival of F. heteroclitus only in the M2 group compared with the control; the hatching rate was unaffected. Moreover, increases in the local expression of the melatonin receptor (mtnr) gene during follicle maturation were found; however, there were no differences between the experimental groups. Furthermore, in vitro melatonin-treated follicles showed a significantly higher germinal vesicle break down percentage compared with the control, while SDS-PAGE showed no difference in the electrophoretic pattern of the major yolk proteins. Nevertheless, densitometry revealed a greater intensity of the 118-, 95- and 40-kDa components in groups treated with melatonin. Finally, Fourier transform infrared microspectroscopy was applied to classify the different stages of oocyte development (Stages I-II, III and IV) on the basis of their macromolecular composition. The effects induced by melatonin on oogenesis were investigated by comparing vibrational spectra of females exposed to melatonin with those of controls. Changes to the Amide I band, corresponding to an increase in ß-structure, were found in oocytes of females exposed to the highest melatonin dose. These results highlight the positive role of melatonin, which is able to enhance the reproductive capacity of F. heteroclitus. Further studies are in progress to better explain the molecular mechanisms by which melatonin treatment affects reproduction in this marine species.


Assuntos
Fundulidae/fisiologia , Melatonina/farmacologia , Reprodução/efeitos dos fármacos , Animais , Relação Dose-Resposta a Droga , Proteínas do Ovo/metabolismo , Eletroforese em Gel de Poliacrilamida , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/metabolismo , Feminino , Fertilidade/efeitos dos fármacos , Proteínas de Peixes/efeitos dos fármacos , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Fundulidae/genética , Fundulidae/metabolismo , Masculino , Microespectrofotometria , Oócitos/efeitos dos fármacos , Oócitos/metabolismo , Oogênese/efeitos dos fármacos , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Receptores de Melatonina/efeitos dos fármacos , Receptores de Melatonina/genética , Receptores de Melatonina/metabolismo , Reprodução/genética , Espectroscopia de Infravermelho com Transformada de Fourier , Fatores de Tempo , Técnicas de Cultura de Tecidos
5.
Artigo em Inglês | MEDLINE | ID: mdl-36554488

RESUMO

BACKGROUND: Cancer is very disruptive in adolescence and hospitalizations interfere with this development stage in becoming independent, developing social relationships, and making plans for the future. A major challenge in the care of adolescents with cancer is being able to enhance their quality of life. The aim of this project is to increase our understanding of how adventure therapy influenced quality of life for adolescents with cancer. METHODS: Bambino Gesù Children's Hospital, in collaboration with the Tender to Nave Italia Foundation (TTNI), has been conducting a unique project, located on a beautiful brigantine of the Italian Navy. Adventure therapy is a form of experiential therapy that consists of various types of adventure, in particular outdoor and sailing activities. Ninety teenagers have been the protagonists of this project to date and filled out two questionnaires about quality of life and self-esteem, before and after the sailing experience. RESULTS: The adventure provides the opportunity for the participants to build interpersonal relationships and develop life skills that they can benefit from in the future experiences. All participants report a significant improvement in their quality of life and self-esteem at the end of this experience. CONCLUSION: This collaborative adventure project is a great way to learn and practice new behaviors, improve interpersonal skills, heal painful emotions, overcome personal obstacles and challenges, and help the teenagers to resume their developmental path after an onco-hematological diagnosis.


Assuntos
Neoplasias , Esportes , Criança , Adolescente , Humanos , Qualidade de Vida , Relações Interpessoais , Habilidades Sociais
6.
Analyst ; 135(12): 3213-9, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20953511

RESUMO

Fourier transform infrared (FTIR) microspectroscopy has been employed to investigate benign (ordinary dermal and Reed nevi), dysplastic and malignant (invasive melanoma) skin lesions through the analysis of spectral changes of melanocytes as well as in the evaluation of the presence of melanin. Hierarchical cluster analysis and principal component analysis led to a satisfactory separation of malignant from dysplastic and normal melanocytes. Also, on enlarging the clustering with spectra from Reed and dermal nevi, the multivariate analysis segregated well the spectral data into discrete clusters, allowing the obtaining of reliable average spectra for analysis at the molecular level of the main groups or components responsible for the biological and biochemical changes. The most significant spectral characteristics appear to be related to differences in secondary protein structures, in nucleic acid conformation, in intra- and intermolecular bonding. In all cases, supervised and unsupervised spectral analyses resulted in satisfactory agreement with histopathological findings.


Assuntos
Melanócitos , Melanoma , Microscopia/métodos , Nevo , Neoplasias Cutâneas , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Análise por Conglomerados , Humanos , Melanócitos/química , Melanócitos/citologia , Melanócitos/patologia , Melanoma/química , Melanoma/patologia , Análise Multivariada , Nevo/química , Nevo/patologia , Análise de Componente Principal , Conformação Proteica , Proteínas/química , Neoplasias Cutâneas/química , Neoplasias Cutâneas/patologia
7.
Anal Bioanal Chem ; 398(7-8): 3063-72, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20936269

RESUMO

The aim of this study was to verify the effects of probiotic Lactobacillus rhamnosus on zebrafish oocyte maturation using FPA (focal plane array) FTIR imaging together with specific biochemical assays (SDS-PAGE, real-time PCR and enzymatic assay). Oocyte growth is prevalently due to a vitellogenic process which consists of the hepatic synthesis of vitellogenin and its selective uptake during maturation. The administration of L. rhamnosus IMC 501 for 10 days induced chemical changes to oocyte composition, promoting the maturation process. Some interesting biochemical features, linked to protein secondary structure (amide I band) and to phospholipidic and glucidic patterns, were detailed by vibrational analysis. The spectroscopic results were supported by the early increase of the lysosomal enzyme involved in the final oocyte maturation, the cathepsin L. This enzyme increases during follicle maturation, with the highest levels in class IV oocytes. In treated females, class III oocytes showed higher cathepsin L gene expression and enzymatic activity, with levels comparable to class IV oocytes isolated from controls; this can be related to the proteolytic cleavage of the higher molecular mass yolk protein components, as evidenced by SDS-PAGE.


Assuntos
Lacticaseibacillus rhamnosus/fisiologia , Oócitos/microbiologia , Probióticos/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Animais , Catepsina L/genética , Catepsina L/fisiologia , Eletroforese em Gel de Poliacrilamida , Feminino , Oócitos/enzimologia , Oócitos/fisiologia , RNA/química , RNA/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Peixe-Zebra
8.
Aust Orthod J ; 25(1): 34-40, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19634462

RESUMO

OBJECTIVE: To investigate the short-term optical, chemical and morphological changes in Invisalign appliances. METHODS: One 'as-received' Invisalign aligner, one 'as-received' Invisalign aligner immersed in artificial saliva for 14 days and 10 Invisalign aligners worn by 10 randomly selected patients for 14 days were used. Fourier'transform infra-red microspectroscopy was used to characterise any molecular changes on the surfaces of the appliances, spectrophotometry was used to evaluate any changes in colour and transparency, scanning electron microscopy and energy dispersive X-ray microanalysis were used to examine the surface morphology and elemental composition of deposits on the surfaces of the aligners and gas chromatography-mass spectrometry was used to identify substances released from the aligners into the artificial saliva. RESULTS: Aligners worn for 14 days had microcracks, abraded and delaminated areas, localised calcified biofilm deposits and loss of transparency. Monomers and/or by-products were not released from the aligner suspended in artificial saliva for 14 days, which suggests that the material is chemically stable. CONCLUSIONS: Further studies are required to evaluate how intra-oral conditions may influence the optical properties and chemical stability of the aligners.


Assuntos
Aparelhos Ortodônticos Removíveis , Microanálise por Sonda Eletrônica , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Fenômenos Ópticos , Saliva Artificial , Espectroscopia de Infravermelho com Transformada de Fourier , Fatores de Tempo
9.
Recenti Prog Med ; 109(10): 487-493, 2018 Oct.
Artigo em Italiano | MEDLINE | ID: mdl-30394410

RESUMO

The high rates of psychological distress, disability and/or chronic illness reported among children, adolescents and young adults, are a recent stimulus for the development and evaluation of new initiatives. Adventure therapy, realized through sailing navigation or stay in the mountains are effective strategies to raise the welfare of the beneficiaries, implementing self-esteem, autonomy and social skills. A "Nave Italia" model is described and prospects for development in a sector not yet capable to produce high quality research and training, according to traditional gold standard criteria by medical research, are discussed.


Assuntos
Terapias Complementares/métodos , Estresse Psicológico/terapia , Meio Selvagem , Adolescente , Criança , Doença Crônica/psicologia , Pessoas com Deficiência/psicologia , Humanos , Autonomia Pessoal , Recreação , Autoimagem , Habilidades Sociais , Estresse Psicológico/psicologia , Adulto Jovem
10.
Recenti Prog Med ; 109(3): 164-165, 2018 03.
Artigo em Italiano | MEDLINE | ID: mdl-29565049

RESUMO

Humans are influenced by irrational preferences in making choices, so that clinicians also are prone to irrational decision-making. Exhaustive information about the value of therapies are frequently unavailable, full results of intervention trials are often hidden, conclusive evidence is highly desirable but it is seldom accessible. Healthcare could benefit from the new ways of approaching the decision framework due to behavioral economists: understanding the hidden traps in decision-making and the way the human brain works is an essential step and the best protection from biases is always awareness.


Assuntos
Comportamento de Escolha , Tomada de Decisões , Médicos/organização & administração , Viés , Atenção à Saúde/organização & administração , Atenção à Saúde/normas , Humanos
11.
Recenti Prog Med ; 109(6): 319-321, 2018 Jun.
Artigo em Italiano | MEDLINE | ID: mdl-29968858

RESUMO

Several new health technologies are going to be introduced in the healthcare system, as well as new ways of making diagnoses, new drugs, new strategies for customizing therapy. Introducing innovation requires a considerable effort from healthcare decision-makers. In fact, every innovation may have an impact in terms of altering diagnostic and clinical pathways, but also in terms of processes, organizational structures, services and interventions delivery, costs. Facing these continuous changes, we need to support the growth of leading doctors: leadership development should start during medical school. Health systems should identify potential leaders, characterized by intelligence, deep medical culture, humanity and passion, involving them in task forces, committees, periodic retreat teams protected by the pharmaceutical industry influence, experiential training programs. Being trained on organizational, communication and team-building aspects, new medical leaders can master core competencies such as strategic planning and change management. Continuous support, through a system of tutoring by other leaders, will increase emotional intelligence, facilitating decision-making processes and improving communication and collaboration skills. Adopting strategies like those described, the health system will achieve the efficiency and organizational effectiveness needed to prevent waste and to grant the benefits of pharmacological and technological innovation to all the stakeholders.


Assuntos
Atenção à Saúde/organização & administração , Educação Médica/métodos , Programas Nacionais de Saúde/organização & administração , Médicos/normas , Tecnologia Biomédica/tendências , Comunicação , Comportamento Cooperativo , Tomada de Decisões , Atenção à Saúde/tendências , Humanos , Liderança , Programas Nacionais de Saúde/tendências
12.
Nanotoxicology ; 10(4): 462-70, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26444575

RESUMO

Biomolecular profiling with Fourier-Transform InfraRed Microscopy was performed to distinguish the Zn(2+)-mediated effects on the crustacean (Porcellio scaber) digestive glands from the ones elicited by the ZnO nanoparticles (NPs). The exposure to ZnO NPs or ZnCl2 (1500 and 4000 µg Zn/g of dry food) activated different types of metabolic pathways: some were found in the case of both substances, some only in the case of ZnCl2, and some only upon exposure to ZnO NPs. Both the ZnO NPs and the ZnCl2 increased the protein (∼1312 cm(-1); 1720-1485 cm(-1)/3000-2830 cm(-1)) and RNA concentration (∼1115 cm(-1)). At the highest exposure concentration of ZnCl2, where the effects occurred also at the organismal level, some additional changes were found that were not detected upon the ZnO NP exposure. These included changed carbohydrate (most likely glycogen) concentrations (∼1043 cm(-1)) and the desaturation of cell membrane lipids (∼3014 cm(-1)). The activation of novel metabolic pathways, as evidenced by changed proteins' structure (at 1274 cm(-1)), was found only in the case of ZnO NPs. This proves that Zn(2+) are not the only inducers of the response to ZnO NPs. Low bioavailable fraction of Zn(2+) in the digestive glands exposed to ZnO NPs further supports the role of particles in the ZnO NP-generated effects. This study provides the evidence that ZnO NPs induce their own metabolic responses in the subtoxic range.


Assuntos
Sistema Digestório/efeitos dos fármacos , Sistema Digestório/metabolismo , Isópodes/efeitos dos fármacos , Nanopartículas/efeitos adversos , Óxido de Zinco/administração & dosagem , Óxido de Zinco/efeitos adversos , Animais , Cloretos/efeitos adversos , Isópodes/metabolismo , Microscopia , Nanopartículas/administração & dosagem , Transdução de Sinais/efeitos dos fármacos , Espectroscopia de Infravermelho com Transformada de Fourier , Compostos de Zinco/efeitos adversos
13.
Fertil Steril ; 101(1): 120-7, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24140036

RESUMO

OBJECTIVE: To characterize from a vibrational point of view the alterations caused by aging on human oocytes. DESIGN: Reproductive biology. SETTING: Private assisted reproductive technology clinic, synchrotron beam line, and university infrared laboratory. PATIENT(S): Twenty women of different ages (30 ± 2 and 39 ± 2 years) selected on the basis of detailed inclusion criteria and submitted to controlled ovarian stimulation according to a specific protocol. INTERVENTION(S): Collection of 68 supernumerary oocytes that were not used during the IVF cycle from the above cited consenting patients. MAIN OUTCOME MEASURE(S): Focal Plane Array Fourier transform infrared (FTIR) analysis of human oocytes. RESULT(S): Specific spectral differences were highlighted in the two experimental groups of oocytes. In particular, in oocytes of 39-year-old women, the occurrence of peroxidative processes and a decrease in the amount of carbohydrates were observed, together with alterations in the phospholipid membrane, proteic pattern, and nucleic acids content. CONCLUSION(S): For the first time, FTIR spectroscopy was applied to human oocytes, leading to strong evidence of damage from aging in the gametes of mature women, which could be related to a decline in reproductive function. All the information obtained may be considered useful to improve the scientific knowledge on human reproduction and to exploit new strategies for detecting oocyte aging.


Assuntos
Envelhecimento/metabolismo , Senescência Celular/fisiologia , Oócitos/metabolismo , Técnicas de Reprodução Assistida , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Adulto , Envelhecimento/patologia , Feminino , Humanos , Oócitos/patologia
15.
Chem Phys Lipids ; 163(6): 601-6, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20435025

RESUMO

The combined effect of trehalose and temperature on the wetting properties of L-alpha-dioleoyl-phosphatidyl-choline (DOPC) model membranes in excess aqueous solutions has been analyzed by X-ray diffraction and extended electron density map reconstruction. At room temperature, DOPC in excess water forms a fluid lamellar L(alpha) phase. In the presence of trehalose, no phase transitions occur, but repeat and intermembrane distances increase considerably. Electron density maps show that trehalose in solution promotes a straightening of the hydrocarbon chain packing and a reduction of the molecular average area at the polar-apolar interface. Accordingly, the increased intermembrane distance is interpreted as a clear indication of a sugar screening effect of the van der Waals attractive contribution in the lamellar stacks, which overcomes the eventual decreasing of the repulsive fluctuations due to the hardening of the bilayer. By contrast to the thermally induced membrane swelling observed in excess water, in the presence of trehalose the DOPC bilayer thickness and repeat and intermembrane distances decrease continuously with temperature. While the thermal dependence of bilayer thickness is a consequence of the chain conformational disorder promoted by temperature, the changes in the intermembrane distance can be explained only assuming a trehalose-induced re-setting of the long-range force balance. The final results confirm the complex mechanism by which trehalose stabilize lipid bilayers.


Assuntos
Bicamadas Lipídicas/química , Fosfatidilcolinas/química , Trealose/química , Agentes Molhantes/química , Temperatura , Água/química , Difração de Raios X
16.
Microsc Res Tech ; 72(2): 67-75, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18825780

RESUMO

On continuing our studies on head and neck neoplasia, specimens from salivary gland tumors have been explored by using infrared microimaging spectroscopy to discern healthy from neoplastic tissues. Samples with Warthin tumor, epithelial displasia, marginal B-cell lymphoma, low-grade adenocarcinoma, and adenoid cystic carcinoma pathologies have been investigated by using conventional light sources. Changes were monitored at the molecular level, probing spectral markers such as Amide I and II, phosphate, nucleic acids, and carbohydrates vibrational modes. In all cases, supervised and unsupervised spectral analyses resulted in satisfactory agreement with histopathological findings.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Reconhecimento Automatizado de Padrão/métodos , Neoplasias das Glândulas Salivares/patologia , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Biomarcadores Tumorais/análise , Análise por Conglomerados , Humanos , Distribuição Normal , Análise de Componente Principal , Neoplasias das Glândulas Salivares/química , Glândulas Salivares/química , Glândulas Salivares/patologia
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