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1.
Nat Commun ; 10(1): 5523, 2019 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-31797931

RESUMO

Active thermal imaging is a valuable tool for the nondestructive characterization of the morphological properties and the functional state of biological tissues and synthetic materials. However, state-of-the-art techniques do not typically combine the required high spatial resolution over extended fields of view with the quantification of temperature variations. Here, we demonstrate quantitative far-infrared photo-thermal imaging at sub-diffraction resolution over millimeter-sized fields of view. Our approach combines the sample absorption of modulated raster-scanned laser light with the automated localization of the laser-induced temperature variations imaged by a thermal camera. With temperature increments ∼0.5-5 °C, we achieve a six-time gain with respect to our 350-µm diffraction-limited resolution with proof-of-principle experiments on synthetic samples. We finally demonstrate the biological relevance of sub-diffraction thermal imaging by retrieving temperature-based super-resolution maps of the distribution of Prussian blue nanocubes across explanted murine skin biopsies.

2.
J Prev Med Hyg ; 59(2): E107-E119, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30083617

RESUMO

Combination vaccines represent a valuable technological innovation in the field of infectious disease prevention and public health, because of their great health and economic value from the individual, societal, and healthcare system perspectives. In order to increase parents' and healthcare professionals' confidence in the vaccination programs and maintain their benefits to society, more information about the benefits of innovative vaccination tools such as combination vaccines is needed. Purpose of this work is an examination of available hexavalent vaccines, that protect against Diphtheria, Tetanus, Pertussis, Poliomyelitis, Hepatitis B and Haemophilus influenzae type b infections. From the epidemiological updates of vaccine preventable diseases to the vaccine development cycle, from the immunogenicity of antigenic components to the safety and co-administration with other vaccines, several aspects of available hexavalent vaccines are discussed and deepened. Also a number of practical considerations on schedules, age of employment, strategies for vaccination recovery, vaccination in at-risk births are issued, based on the recommendations of Italian Ministry of Health, Italian Society of Pharmacology (SIF), Italian Society for Pediatrics (SIP), Italian Federation of Family Paediatricians (FIMP) and Italian Society of Hygiene, Preventive Medicine and Public Health (SItI).


Assuntos
Controle de Doenças Transmissíveis , Consenso , Vacina contra Difteria, Tétano e Coqueluche/administração & dosagem , Vacina contra Difteria, Tétano e Coqueluche/provisão & distribuição , Vacinas contra Hepatite B/administração & dosagem , Vacinas contra Hepatite B/provisão & distribuição , Segurança do Paciente , Vacina Antipólio de Vírus Inativado/administração & dosagem , Vacina Antipólio de Vírus Inativado/provisão & distribuição , Indústria Farmacêutica , Feminino , Humanos , Itália , Masculino , Gravidez
3.
Sci Rep ; 8(1): 6314, 2018 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-29666438

RESUMO

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.

4.
Sci Rep ; 7(1): 17468, 2017 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-29234132

RESUMO

Second Harmonic Generation (SHG) is a label-free imaging method used to monitor collagen organization in tissues. Due to its sensitivity to the incident polarization, it provides microstructural information otherwise unreachable by other intensity based imaging methods. We develop and test a Microscopic Multiparametric Analysis by Phasor projection of Polarization-dependent SHG (µMAPPS) that maps the features of the collagen architecture in tissues at the micrometer scale. µMAPPS retrieves pixel-by-pixel the collagen fibrils anisotropy and orientation by operating directly on two coupled phasor spaces, avoiding direct fitting of the polarization dependent SHG signal. We apply µMAPPS to fixed tissue sections and to the study of the collagen microscopic organization in tumors ex-vivo and in-vivo. We develop a clustering algorithm to automatically group pixels with similar microstructural features. µMAPPS can perform fast analyses of tissues and opens to future applications for in-situ diagnosis of pathologies and diseases that could assist histo-pathological evaluation.


Assuntos
Colágeno/metabolismo , Microscopia de Geração do Segundo Harmônico/métodos , Algoritmos , Animais , Biópsia , Linhagem Celular Tumoral , Análise por Conglomerados , Colágeno/química , Simulação por Computador , Feminino , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Transplante de Neoplasias , Reconhecimento Automatizado de Padrão/métodos , Processamento de Sinais Assistido por Computador , Software , Cauda , Tendões
5.
Acta Paediatr ; 106(10): 1564-1568, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28580602

RESUMO

AIM: Alleviating pain in neonates should be the goal of all caregivers. We evaluated whether recorded maternal voices were safe and effective in limiting pain in preterm infants undergoing heel lance procedures in the neonatal intensive care unit of an Italian children's hospital. METHODS: This prospective, controlled study took place from December 2013 to December 2015. We enrolled 40 preterm infants, born at a 26-34 weeks of gestation, at a corrected gestational age 29-36 weeks and randomised them to listen or not listen to a recording of their mother's voice during a painful, routine heel lance for blood collection. Changes in the infants' Premature Infant Pain Profile, heart rate, oxygen saturation and blood pressure during the procedure were compared by analysis of variance. Possible side effects, of apnoea, bradycardia, seizures and vomiting, were also recorded. RESULTS: Both groups showed a marked increase in PIPP scores and decrease in oxygen saturation during the procedure, but infants in the treatment group had significantly lower PIPP scores (p = 0.00002) and lower decreases in oxygen saturation (p = 0.0283). No significant side effects were observed. CONCLUSION: Using recorded maternal voices to limit pain in preterm infants undergoing heel lance procedures appeared safe and effective.


Assuntos
Terapia Intensiva Neonatal/métodos , Manejo da Dor/métodos , Recursos Audiovisuais , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Comportamento Materno , Medição da Dor , Estudos Prospectivos , Voz
6.
Ann Oncol ; 27(6): 1062-1067, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26916096

RESUMO

BACKGROUND: Objective response to dacarbazine, the intravenous form of temozolomide (TMZ), in metastatic colorectal cancer (mCRC) is confined to tumors harboring O(6)-methylguanine-DNA-methyltransferase (MGMT) promoter hypermethylation. We conducted a phase II study of TMZ enriched by MGMT hypermethylation in archival tumor (AT), exploring dynamic of this biomarker in baseline tumor (BT) biopsy and plasma (liquid biopsy). PATIENTS AND METHODS: We screened 150 mCRC patients for MGMT hypermethylation with methylation-specific PCR on AT from FFPE specimens. Eligible patients (n = 29) underwent BT biopsy and then received TMZ 200 mg/m(2) days 1-5 q28 until progression. A Fleming single-stage design was used to determine whether progression-free survival (PFS) rate at 12 weeks would be ≥35% [H0 ≤ 15%, type I error = 0.059 (one-sided), power = 0.849]. Exploratory analyses included comparison between MGMT hypermethylation in AT and BT, and MGMT methylation testing by MethylBEAMing in solid (AT, BT) and LB with regard to tumor response. RESULTS: The PFS rate at 12 weeks was 10.3% [90% confidence interval (CI) 2.9-24.6]. Objective response rate was 3.4% (90% CI 0.2-15.3), disease control rate 48.3% (90% CI 32.0-64.8), median OS 6.2 months (95% CI 3.8-7.6), and median PFS 2.6 months (95% CI 1.4-2.7). We observed the absence of MGMT hypermethylation in BT in 62.7% of tumors. CONCLUSION: Treatment of mCRC with TMZ driven by MGMT promoter hypermethylation in AT samples did not provide meaningful PFS rate at 12 weeks. This biomarker changed from AT to BT, indicating that testing BT biopsy or plasma is needed for refined target selection.


Assuntos
Neoplasias Colorretais/tratamento farmacológico , Metilação de DNA/genética , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Dacarbazina/análogos & derivados , Proteínas Supressoras de Tumor/genética , Adulto , Idoso , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/genética , Biópsia , Neoplasias Colorretais/sangue , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Metilases de Modificação do DNA/sangue , Enzimas Reparadoras do DNA/sangue , Dacarbazina/administração & dosagem , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Regiões Promotoras Genéticas , Temozolomida , Proteínas Supressoras de Tumor/sangue
7.
Minerva Pediatr ; 66(6): 549-57, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25336097

RESUMO

The most common causes of nasal obstruction and runny nose in infants and children are infections, mainly of viral origin, or allergies. In neonates and infants viral upper respiratory tract infections (URTI) are frequently observed during episodes of nasal obstruction. Saline irrigation of the nose is believed to alleviate URTI symptoms by helping to eliminate excess mucus, to reduce congestion and by contributing to improve breathing. Objective of the study was to review the efficacy and safety of non-pharmacological options for the treatment of nasal congestion and its sequelae, in infants and children, with a special focus on hypertonic and isotonic solutions and other medical devices, including nasal aspirators. Available data indicate that nasal symptoms in children with allergic rhinitis or acute sinusitis significantly improved following nasal saline irrigation. The use of medical devices is less documented. Nasal aspiration with a medical device, associated with an isotonic saline solution, during viral rhinitis, has been shown to lower the risk of developing acute otitis media and rhinosinusitis, in comparison with a group treated with physiological saline solution alone. Safety and tolerability have been evaluated and no serious adverse events have been reported. Literature data highlighted the good tolerability. The use of isotonic and hypertonic saline solutions to relief nasal congestion in infants and children is widespread; it is a safe and valuable therapeutic support, and can reduce the use of medications (antihistamines, decongestant, antibiotics, corticosteroids) during the treatment of URTIs.


Assuntos
Obstrução Nasal/terapia , Rinite/terapia , Sinusite/terapia , Criança , Humanos , Lactente , Recém-Nascido , Obstrução Nasal/etiologia , Obstrução Nasal/patologia , Infecções Respiratórias/patologia , Infecções Respiratórias/terapia , Rinite/patologia , Sinusite/patologia , Cloreto de Sódio/administração & dosagem , Cloreto de Sódio/química , Irrigação Terapêutica/métodos
8.
J Phys Chem B ; 115(34): 10311-21, 2011 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-21736327

RESUMO

The photodynamics of the Green Fluorescent Protein (GFP) has been addressed in detail, particularly by means of Fluorescence Correlation Spectroscopy (FCS), a technique that provides direct information when the diffusion and the photodynamics time scales are well separated. Efficient photoswitchable GFPs, a crucial component for applications in nanoscopy imaging, have long residence times in the dark state, typically longer than the diffusion time of the protein through the observation volume. In these cases, the effect of the coupling between photodynamics and the diffusion process on the analysis of the FCS measurements cannot be disregarded, and the use of FCS methods becomes therefore critical. This work deals with the analytical and simulative study of such coupling and indicates that the corrections to be applied to the conventional decoupled FCS model scale as the square root of the ratio between the diffusion and the dark state relaxation times. We discuss the possibility to estimate the extent of the diffusion/photodynamics coupling from the analysis of the inverse of the fluorescence autocorrelation function g(t), defined as G(-1)(g(t)) = g(0)/g(t) - 1. The function G(-1)(g(t)) is analyzed in terms of a parabolic expansion in which the curvature term directly provides the desired measure of the coupling. We validate the analytical prediction and the graphical estimate of the coupling on simulations of FCS experiments that are based on a coupled Monte Carlo-Brownian Dynamics algorithm. The analysis of the curvature of G(-1)(g(t)), applied to experimental FCS data of the photoswitchable E222Q mutant of GFPMut2 (Mut2Q), indicates that the trapping rate for this chromophore is 3 orders of magnitude underestimated when the diffusion/photodynamics coupling is not taken into account and sheds some additional light on the complex energy diagram for this protein.


Assuntos
Proteínas de Fluorescência Verde/metabolismo , Luz , Método de Monte Carlo , Espectrometria de Fluorescência/métodos , Algoritmos , Escuridão , Difusão/efeitos da radiação , Proteínas de Fluorescência Verde/genética , Mutação , Fatores de Tempo
9.
Chem Commun (Camb) ; 47(4): 1315-7, 2011 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-21082071

RESUMO

Asymmetric branched gold nanoparticles are obtained using for the first time in the seed-growth approach a zwitterionic surfactant, laurylsulfobetaine, whose concentration in the growth solution allows to control both the length to base-width ratio of the branches and the LSPR position, that can be tuned in the 700-1100 nm near infrared range.


Assuntos
Ouro/química , Nanopartículas Metálicas/química , Tensoativos/química , Nanopartículas Metálicas/ultraestrutura , Espectrofotometria Ultravioleta , Ressonância de Plasmônio de Superfície
10.
Minerva Pediatr ; 62(3 Suppl 1): 25-7, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21089714

RESUMO

The registry is an European, multicentre, prospective and longitudinal study which follows a cohort of children born to mothers with antiphospholipid syndrome (APS). In this article we report preliminary results obtained from 138 mothers and 141 babies (three twin pregnancies). At birth, 16.3% of neonates were less than 37 weeks of gestation and 17% were low birth weight; in addition, 11.3% of neonates were small for gestational age. No cases of neonatal thrombosis were observed. During follow-up period five children showed behavioral abnormalities. A long term clinical follow-up will be necessary to evaluate the neuropsychological development of these children.


Assuntos
Síndrome Antifosfolipídica/epidemiologia , Complicações na Gravidez/epidemiologia , Resultado da Gravidez , Sistema de Registros , Anticorpos Antifosfolipídeos/sangue , Transtorno Autístico/epidemiologia , Transtorno Autístico/etiologia , Pré-Escolar , Europa (Continente) , Feminino , Seguimentos , Humanos , Imunidade Materno-Adquirida , Lactente , Recém-Nascido de Baixo Peso , Recém-Nascido , Recém-Nascido Pequeno para a Idade Gestacional , Recém-Nascido de muito Baixo Peso , Deficiências da Aprendizagem/epidemiologia , Deficiências da Aprendizagem/etiologia , Gravidez , Gravidez Múltipla , Nascimento Prematuro/epidemiologia , Estudos Prospectivos , Transtornos Psicomotores/epidemiologia , Transtornos Psicomotores/etiologia , Trombose/congênito , Trombose/epidemiologia , Gêmeos
11.
Minerva Pediatr ; 62(5): 499-505, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20940683

RESUMO

The main functions of the nasal airway are respiration and olfaction. The nose and sinuses condition air before reaching the lower respiratory tract by providing almost 100% humidification, warming, filtering and trapping of foreign particles. The airway epithelium contributes to the host defense system. Any alteration of this clearance system may produce significant problems, particularly in neonates, who are obligate nasal breathers until they are at least two months old. Nasal obstruction, and the inability to remove nasal secretion by nose blowing, may have serious consequences, such as respiratory distress or discomfort, altered sleep cycle, increased risk of obstructive apnoea and feeding difficulties. Most cases of nasal obstruction in neonates and infants are due to generalized nasal airway obstruction associated with neonatal rhinitis, viral upper respiratory tract infections, and possibly milk/soy allergies. Saline nasal lavage is recommended as an adjunct therapy for rhinosinusitis and allergic rhinitis, and in most cases of nasal congestion or obstruction in newborns, infants and children. In two recent experiences, was deemed to be the Narhinel method safe and effective for treatment of nasal congestion in babies with viral infections of the upper respiratory tract, or for the prevention of acute otitis media (AOM) and acute rhinosinusitis (AR) in children. Due to the efficacy, ease of use, tolerability and the lack of alternative medications in children younger than 12 years of age, nasal irrigation with physiological saline solution, followed by gentle aspiration, represent an effective method for the prevention and control of nasal congestion or obstruction in term or preterm neonates, infants and children.


Assuntos
Obstrução Nasal , Humanos , Lactente , Recém-Nascido , Obstrução Nasal/diagnóstico , Obstrução Nasal/terapia , Cloreto de Sódio , Sucção , Irrigação Terapêutica
12.
J Phys Chem B ; 112(29): 8806-14, 2008 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-18582099

RESUMO

GFP mutants are known to display fluorescence flickering, a process that occurs in a wide time range. Because serine 65, threonine 203, glutamate 222, and histidine 148 have been indicated as key residues in determining the GFP fluorescence photodynamics, we have focused here on the role of histidine 148 and glutamate 222 by studying the fluorescence dynamics of GFPmut2 (S65A, V68L, and S72A GFP) and its H148G (Mut2G) and E222Q (Mut2Q) mutants. Two relaxation components are found in the fluorescence autocorrelation functions of GFPmut2: a 10-100 micros pH-dependent component and a 100-500 micros laser-power-dependent component. The comparison of these three mutants shows that the mutation of histidine 148 to glycine induces a 3-fold increase in the protonation rate, thereby indicating that the protonation-deprotonation of the chromophore occurs via a proton exchange with the solution mediated by the histidine 148 residue. The power-dependent but pH-independent relaxation mode, which is not affected by the E222Q and H148G mutations, is due to an excited-state process that is probably related to conformational rearrangements of the chromophore after the photoexcitation, more than to the chromophore excited-state proton transfer.


Assuntos
Proteínas de Fluorescência Verde/química , Substâncias Luminescentes/química , Fótons , Prótons , Simulação por Computador , Ácido Glutâmico/química , Histidina/química , Concentração de Íons de Hidrogênio , Mutação , Conformação Proteica , Serina/química , Espectrometria de Fluorescência , Treonina/química
13.
Pediatr Med Chir ; 30(6): 306-8, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19431954

RESUMO

Sartans are selective type 1 angiotensin II receptor antagonists that are used for treatment of arterial hypertension. We report a case of severe renal failure required dialysis after the use of olmesartan in the last month of pregnancy. Exposure to sartans during the last period of gestation seems to be associated with high risk of congenital malformations. It is important to stress that the use of these drugs during pregnancy must be avoided, especially in the third trimester.


Assuntos
Bloqueadores do Receptor Tipo 1 de Angiotensina II/efeitos adversos , Feto/efeitos dos fármacos , Hipertensão/tratamento farmacológico , Imidazóis/efeitos adversos , Complicações Cardiovasculares na Gravidez/tratamento farmacológico , Insuficiência Renal/induzido quimicamente , Tetrazóis/efeitos adversos , Adulto , Índice de Apgar , Peso ao Nascer , Evolução Fatal , Feminino , Humanos , Recém-Nascido , Túbulos Renais Proximais/patologia , Gravidez , Insuficiência Renal/patologia
14.
Int J Immunopathol Pharmacol ; 21(4): 781-6, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19144263

RESUMO

Colostrum contains soluble and cellular components, the latter mainly T lymphocytes. We expanded in vitro colostrum T lymphocytes (CoTL) to evaluate phenotype and capability of cytokine production. We also considered paired cord blood T-lymphocytes (CBTL) representing the newborn "virgin" immune system. CoTL showed memory phenotype while CBTL expressed mainly naïve phenotype. CoTL included a balanced percentage of helper and cytotoxic subsets. We observed higher percentages of IL-2 (p=0.003) and IL-4 (p=0.027) producing cells by helper rather than by cytotoxic T lymphocytes. The greatest percentage of IFN-gamma producing cells was in cytotoxic cells (p=0.0048), while no difference was found for IL-10. Cord blood samples consisted of a statistically significant greater percentage of helper than cytotoxic cells (p<0.001), with a low percentage of cytokine producing cells, confirming the immaturity of the newborns immune system. CBTL percentage of IL-2 producing cells was higher for helper than cytotoxic subset (p<0.001). We observed a greater percentage of IFN-gamma (p=0.001), IL-4 (p=0.003) and IL-10 (p<0.001) producing cells by cytotoxic than helper T lymphocytes. CoTL demonstrated to protect the newborn through the mothers previous immune experience and to supply active cytokines, which can help the postnatal development of both T type 1/T type 2 response.


Assuntos
Colostro/imunologia , Citocinas/imunologia , Recém-Nascido/imunologia , Linfócitos T/imunologia , Colostro/citologia , Citometria de Fluxo , Humanos
15.
Stress ; 10(4): 342-50, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17853063

RESUMO

TRAP-1 is a mitochondrial heat shock protein (HSP), recently identified in Saos-2 osteosarcoma cells adapted to mild oxidative stress induced by diethylmaleate (DEM). TRAP-1 mRNA expression is increased in DEM-adapted cells as well as in tumor cells resistant to 5-fluorouracil and to platin derivatives. Since a strong decrease of TRAP-1 protein levels, upon cisplatin treatment, is observed only in controls but not in the DEM-adapted counterpart, a possible role for this protein in the development of resistant phenotypes could be hypothesized. To characterize the protective role of TRAP-1 against oxidative stress and apoptosis, stable transfectants were generated and characterized for their response to different stress types. These stable clones expressing constitutively high TRAP-1 levels: (i) are more resistant to H2O2-induced DNA damage and to apoptosis by cisplatin; (ii) contain higher reduced glutathione (GSH) levels than control cells; and (iii) do not release the apoptosis-inducing factor into the nucleus upon cisplatin treatment. Furthermore, high TRAP-1 levels interfere with caspase 3 activation. These results confirm the anti-apoptotic role of TRAP-1, and suggest that increased expression of this mitochondrial HSP in DEM-adapted and chemoresistant cells could be part of a pro-survival signaling pathway aimed to evade toxic effects of oxidants and anticancer drugs.


Assuntos
Apoptose , Proteínas de Choque Térmico HSP90/fisiologia , Estresse Oxidativo , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Cisplatino/farmacologia , Ensaio Cometa , Resistencia a Medicamentos Antineoplásicos , Proteínas de Choque Térmico HSP90/metabolismo , Humanos , Peróxido de Hidrogênio/farmacologia , Proteínas Mitocondriais/metabolismo , Modelos Biológicos , Osteossarcoma/patologia , Espécies Reativas de Oxigênio , Sais de Tetrazólio/farmacologia , Tiazóis/farmacologia
16.
Lupus ; 16(2): 129-32, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17402369

RESUMO

Immunosuppressive drugs given during pregnancy to mothers suffering from a systemic autoimmune disease (AID) can cross the placenta, thus being potentially able to affect the offspring immune system. Aim of our study was to evaluate the in vivo immune function of a series of these newborns. Twenty-two babies born from mothers suffering from autoimmune diseases (AID) who had been taking immunosuppressive drugs during pregnancy were evaluated for their response to vaccination with C. Tetani toxoid. Six babies born from mothers receiving low-dose aspirin only were used as controls. The immune response to C. Tetani vaccination was evaluated with an ELISA to detect circulating antibodies. Five children out of 28 (17%) did not achieve a protective titer of anti C. Tetani toxoid IgG. No clear relationship was found between specific drug exposure and antibody response. Our findings suggest that maternal immunosuppressive treatment given for a systemic AID can affect the response to an active immunization, without specificities for drug types used.


Assuntos
Anticorpos/sangue , Doenças Autoimunes/tratamento farmacológico , Feto/efeitos dos fármacos , Imunossupressores/farmacologia , Toxoide Tetânico/imunologia , Adulto , Feminino , Humanos , Imunossupressores/uso terapêutico , Recém-Nascido , Masculino , Gravidez , Complicações na Gravidez/tratamento farmacológico
17.
Nano Lett ; 7(4): 1070-5, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17346091

RESUMO

An organic dye, SAMSA, bound to gold nanoparticles, displays random photoactivated fluorescence blinking whose rate depends on the size of the nanoparticles. We report experiments indicating that (1) the dye emission wavelength is red-shifted (10-30 nm) by applying an external low voltage (1-10 V) and that (2) the fluorescence emission of single dyes can be resonantly driven by tuning the alternating external bias frequency from 1 to 3 Hz, depending on the nanoparticle size. These properties appear highly valuable and promising for devising light emitting nanostructures.


Assuntos
Corantes Fluorescentes/química , Corantes Fluorescentes/efeitos da radiação , Ouro/química , Nanoestruturas/química , Nanoestruturas/efeitos da radiação , Nanotecnologia/métodos , Espectrometria de Fluorescência/métodos , Sítios de Ligação , Cristalização/métodos , Campos Eletromagnéticos , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Nanoestruturas/ultraestrutura , Tamanho da Partícula , Propriedades de Superfície
18.
J Perinatol ; 27(5): 278-83, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17363909

RESUMO

OBJECTIVE: To evaluate the incidence of electrocardiographic and laboratory abnormalities in neonates born from mothers with connective tissue disease and positive for anti-SSA/Ro antibodies. STUDY DESIGN: Electrocardiogram, blood cell counts, liver and renal function tests prospectively obtained from 51 infants born from anti-SSA/Ro-positive mothers with connective tissue disease were compared with those obtained from 50 control infants born from mothers with anti-extractable nuclear antigen (ENA)-negative connective tissue disease. One infant with congenital complete heart block was excluded from analysis. RESULTS: No infant showed sinus bradycardia. A first-degree atrioventricular block at birth was observed in five study group and no control group infants, P=0.023. Atrioventricular blocks spontaneously reverted or remained stable during the first year of life. Mean corrected QT value of infants born from anti-SSA/Ro-positive mothers was slightly prolonged as compared with the control group (0.404+/-0.03 s vs 0.395+/-0.02 s; P=0.060). CONCLUSIONS: Infants exposed to anti-SSA/Ro antibodies had a significantly higher prevalence of first-degree atrioventricular block. At variance with previous studies, we observed a low frequency of hematologic abnormalities and no cases of hepatobiliary disease.


Assuntos
Anticorpos Antinucleares/sangue , Doenças do Tecido Conjuntivo/diagnóstico , Doenças do Recém-Nascido/diagnóstico , Complicações Hematológicas na Gravidez/diagnóstico , Contagem de Células Sanguíneas , Doenças do Tecido Conjuntivo/imunologia , Eletrocardiografia , Feminino , Seguimentos , Bloqueio Cardíaco/diagnóstico , Bloqueio Cardíaco/imunologia , Humanos , Lactente , Recém-Nascido , Doenças do Recém-Nascido/imunologia , Testes de Função Hepática , Síndrome do QT Longo/diagnóstico , Síndrome do QT Longo/imunologia , Masculino , Gravidez , Complicações Hematológicas na Gravidez/imunologia , Estudos Prospectivos , Remissão Espontânea
19.
J Chemother ; 19 Suppl 2: 28-30, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18073176

RESUMO

Bacterial sepsis remain a major cause of mortality and morbidity in the newborn. The severe outcome of neonatal sepsis, despite the advances in perinatal and neonatal care and use of potent antibiotics, is related to the neonatal reduced immune defenses and the complex interactions between the infecting microorganism and the host responses. An early diagnosis, based on the clinical picture, the isolation of microorganisms and the positivity of inflammatory indexed, is mandatory. A timely treatment should be aimed to the elimination of pathogens with antimicrobials. Intravenous immunoglobulin and hematopoietic growth factors may be considered to improve the disturbed immune homeostases.


Assuntos
Infecções Bacterianas/terapia , Sepse/terapia , Antibacterianos/uso terapêutico , Infecções Bacterianas/diagnóstico , Biomarcadores , Idade Gestacional , Humanos , Imunoglobulina G/uso terapêutico , Imunoglobulinas Intravenosas/uso terapêutico , Recém-Nascido , Reação em Cadeia da Polimerase , Sepse/diagnóstico , Sepse/imunologia
20.
Eur Biophys J ; 35(8): 663-74, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16786346

RESUMO

We have studied the unfolding of single molecules of GFP-mut2 mutant trapped in wet silica gels in a wide range of GuHCl concentration. After the addition of denaturant, the number of fluorescent molecules decreases with unfolding rates (of the order of 0.01 min(-1)) that are in very good agreement with bulk fluorescence and circular dichroism data. Unexpectedly, single molecule experiments show rare fluctuations in the number of fluorescent proteins at equilibrium. On the other hand, although a first approximate description of the number decays can be reasonably performed by single exponential functions, the distributions of the single molecule unfolding times show a maximum at times congruent with 50-100 min up to the denaturation midpoint concentration of [GuHCl] congruent with 2.5 M. A theoretical analysis of the distributions indicates that this feature is a fingerprint of the competition between unfolding and refolding processes when the protein is very far from the midpoint denaturant concentration.


Assuntos
Proteínas de Fluorescência Verde/química , Géis , Proteínas de Fluorescência Verde/genética , Cinética , Mutação , Conformação Proteica , Desnaturação Proteica , Dobramento de Proteína , Sílica Gel , Dióxido de Silício , Espectrometria de Fluorescência
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