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1.
Chem Sci ; 14(22): 5827-5841, 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37293634

RESUMO

In this perspective, we provide an overview of the recent achievements in luminescent lanthanide-based molecular cluster-aggregates (MCAs) and illustrate why MCAs can be seen as the next generation of highly efficient optical materials. MCAs are high nuclearity compounds composed of rigid multinuclear metal cores encapsulated by organic ligands. The combination of high nuclearity and molecular structure makes MCAs an ideal class of compounds that can unify the properties of traditional nanoparticles and small molecules. By bridging the gap between both domains, MCAs intrinsically retain unique features with tremendous impacts on their optical properties. Although homometallic luminescent MCAs have been extensively studied since the late 1990s, it was only recently that heterometallic luminescent MCAs were pioneered as tunable luminescent materials. These heterometallic systems have shown tremendous impacts in areas such as anti-counterfeiting materials, luminescent thermometry, and molecular upconversion, thus representing a new generation of lanthanide-based optical materials.

2.
Chem Commun (Camb) ; 59(92): 13715-13718, 2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-37906523

RESUMO

The impact of composition control and energy transfer on luminescence thermometry was investigated in a TbIII/EuIII dual-emitting molecular cluster-aggregate, known as {Ln20}. The study of lifetime dynamics sheds new light on how one can take advantage of rational planning to enhance thermometric performance and gaining insights into intriguing optical properties.

3.
ACS Appl Mater Interfaces ; 15(37): 44137-44146, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37695985

RESUMO

Composition control is a powerful tool for obtaining high-performance lanthanide (Ln) luminescent materials with adjustable optical outputs. This strategy is well-established for hierarchically structured nanoparticles, but it is rarely applied to molecular compounds due to the limited number of metal centers within a single unit. In this work, we present a series of molecular cluster-aggregates (MCAs) with an icosanuclear core {Ln2Eu2Tb16} (Ln = Ce, Pr, Nd, Sm, Gd, Dy, Ho, Er, Tm, and Yb) in which we explore composition control, akin to nanoparticles, to modulate the optical output. More specifically, we target to understand how the presence of a third LnIII doping ion would impact the well-known TbIII → EuIII energy transfer and the ratiometric optical thermometry performance based on the TbIII/EuIII pair. Photophysical properties at room and at varying temperatures were investigated. Based on experimental data and well-established intrinsic features, such as spin-orbit coupling strength and LnIII 4f energy levels' structure, we discuss the possible luminescent processes present in each MCA and provide insight into qualitative trends that can be rationally correlated throughout the series.

4.
Cureus ; 14(9): e29403, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36304381

RESUMO

Streptococcus pneumoniae (SP) is an uncommon but potentially serious neonatal pathogen. SP is perceived as a significant cause of mortality and morbidity in infancy; however, there are relatively few cases of neonatal sepsis recorded, with an incidence between 1% and 11%. We aim to report the spectrum of morbidity associated with SP infections in the neonatal period. Two cases of neonatal SP infection are reported. The first neonate presented with a very early onset of severe clinical disease with bacteremia and pneumonia. She developed severe pulmonary hypertension and needed intensive ventilatory support, including nitric oxide, and vasoactive drugs. An SP serotype 23B was isolated from blood cultures and bronchial secretions as well as from the mother's vaginal secretions. In the second case, the baby presented with bacteremia and meningitis. He remained hemodynamically stable and did not need respiratory support. Blood and cerebrospinal fluid cultures revealed an SP serotype 8. In both cases, the neonates were treated with vancomycin and cefotaxime. Both mothers remained well and asymptomatic during the perinatal period. These reported cases emphasize the importance of considering a wide range of microorganisms in the differential diagnosis of early-onset neonatal sepsis. Although uncommon, SP can have different clinical manifestations and cause significant diseases in newborns. Specific preventive measures against early-onset sepsis for this pathogen are yet to be implemented due to the absence of sufficient scientific evidence. For this reason, prompt and aggressive treatment remains the best therapeutic approach.

5.
BMC Pediatr ; 11: 112, 2011 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-22151558

RESUMO

BACKGROUND: Most epidemiological studies on pediatric asthma rely on the report of "wheezing" in questionnaires. Our aim was to investigate the understanding of this term by parents and health professionals. METHODS: A cross-sectional survey was carried out in hospital and community settings within the south of Portugal. Parents or caregivers self-completed a written questionnaire with information on social characteristics and respiratory history. Multiple choice questions assessed their understanding of "wheezing". Health professionals (physicians, nurses and physiotherapists) were given an adapted version. We used bivariate analysis and multivariate models to study associations between definitions of "wheezing" and participants' characteristics. RESULTS: Questionnaires from 425 parents and 299 health professionals were included. The term "wheezing" was not recognized by 34% of parents, more frequently those who were younger (OR 0.4 per 10-year increment, 95% CI 0.3-0.7), had lower education (OR 3.3, 95% CI 1.5-7.4), and whose children had no history of respiratory disease (OR 4.6, 95% CI 2.5-8.7) (all ORs adjusted). 31% of parents familiar with "wheezing" either did not identify it as a sound, or did not locate it to the chest, while tactile (40%) and visual (34%) cues to identify "wheezing" were frequently used. Nurses reported using visual stimuli and overall assessments more often than physicians (p < 0.01). The geographical location was independently associated with how parents recognized and described "wheezing". CONCLUSIONS: Different meanings for "wheezing" are recognized in Portuguese language and may be influenced by education, respiratory history and regional terminology. These findings are likely applicable to other non-English languages, and suggest the need for more accurate questionnaires and additional objective measurement instruments to study the epidemiology of wheezing disorders.


Assuntos
Asma/epidemiologia , Conhecimentos, Atitudes e Prática em Saúde , Pessoal de Saúde , Pais , Sons Respiratórios/diagnóstico , Inquéritos e Questionários , Adolescente , Adulto , Asma/complicações , Asma/diagnóstico , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Portugal/epidemiologia , Prevalência , Sons Respiratórios/etiologia , Fatores de Risco , Adulto Jovem
6.
Nanoscale ; 13(35): 14723-14733, 2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34477629

RESUMO

The engineering of core@multi-shell nanoparticles containing heterogeneous crystalline phases in different layers constitutes an important strategy for obtaining optical probes. The possibility of obtaining an opto-magnetic core@multi-shell nanoparticle capable of emitting in the visible and near-infrared ranges by upconversion and downshifting processes is highly desirable, especially when its optical responses are dependent on temperature and magnetic field variations. This work proposes the synthesis of hierarchically structured core@multi-shell nanoparticles of heterogeneous crystalline phases: a cubic core containing DyIII ions responsible for magnetic properties and optically active hexagonal shells, where ErIII, YbIII, and NdIII ions were distributed. This system shows at least three excitation energies located at different biological windows, and its emission intensities are sensitive to temperature and external magnetic field variations. The selected crystalline phases of the core@multi-shell nanoparticles obtained in this work is fundamental to the development of multifunctional materials with potential applications as temperature and magnetic field optical probes.

7.
Pediatr Emerg Care ; 25(4): 244-8, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19382329

RESUMO

AIMS: Characterization of newborn visits to the pediatric emergency department (PED). Analysis of the main illnesses and establishment of association between certain conditions and severity of diseases. METHODS: Retrospective study information concerning newborns (aged <28 days) who presented to the PED of Hospital Central de Faro during 2005. We studied the clinical and demographic data referring to the PED's episode and to perinatal occurrences. RESULTS: A total of 540 neonates visited the PED (1.5% of the total PED use), with an average age of 14.0 days and a slight prevalence of males (53.1%). Of the total visits, 17.2% were primary physician referrals. The chief complaints were jaundice, excessive crying, and rash. Diagnostic tests were requested in 27.2% cases. The major diagnoses were nonapparent disease, infant colics, and physiologic jaundice. In 13.0%, hospital admission was necessary. Newborns with referral, those with less than 37 weeks of gestation and those whose delivery weight was less than 2500 g, were more likely to be admitted. CONCLUSIONS: Most PED visits were because of nonserious diseases, mainly because of insufficient caretaker knowledge and information. This highlights the great need for caretakers' education by health staff. It is also important that physicians are aware of the main illnesses in the newborn period and know how to correctly identify the conditions associated to serious pathology.


Assuntos
Serviço Hospitalar de Emergência/estatística & dados numéricos , Doenças do Recém-Nascido/epidemiologia , Peso ao Nascer , Cuidadores/psicologia , Grupos Diagnósticos Relacionados , Feminino , Gastroenteropatias/diagnóstico , Gastroenteropatias/epidemiologia , Gastroenteropatias/terapia , Idade Gestacional , Mau Uso de Serviços de Saúde/estatística & dados numéricos , Hospitalização/estatística & dados numéricos , Hospitais Urbanos/estatística & dados numéricos , Humanos , Recém-Nascido , Doenças do Recém-Nascido/diagnóstico , Doenças do Recém-Nascido/terapia , Recém-Nascido Prematuro , Doenças do Prematuro/diagnóstico , Doenças do Prematuro/epidemiologia , Doenças do Prematuro/terapia , Infecções/diagnóstico , Infecções/epidemiologia , Infecções/terapia , Icterícia Neonatal/epidemiologia , Icterícia Neonatal/terapia , Masculino , Educação de Pacientes como Assunto , Portugal/epidemiologia , Encaminhamento e Consulta/estatística & dados numéricos , Estudos Retrospectivos
8.
Toxicology ; 413: 24-32, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30528861

RESUMO

Gold nanorods (AuNRs) have been studied extensively in biomedicine due to their biocompatibility and their unique properties. Some studies reported that AuNRs selectively accumulate on cancer cell mitochondria causing its death. However, the immediate effects of this accumulation needed further investigations. In this context, we evaluated the effect of AuNRs on the mitochondrial integrity of isolated rat liver mitochondria. We verified that AuNRs decreased the mitochondrial respiratory ratio by decreasing the phosphorylation and maximal states. Additionally, AuNRs caused a decrease in the production of mitochondrial ROS and a delay in mitochondrial swelling. Moreover, even with cyclosporine A treatment, AuNRs disrupted the mitochondrial potential. With the highest concentration of AuNRs studied, disorganized mitochondrial crests and intermembrane separation were observed in TEM images. These results indicate that AuNRs can interact with mitochondria, disrupting the electron transport chain. This study provides new evidence of the immediate effects of AuNRs on mitochondrial bioenergetics.


Assuntos
Ouro/toxicidade , Mitocôndrias Hepáticas/efeitos dos fármacos , Nanotubos/toxicidade , Consumo de Oxigênio/efeitos dos fármacos , Animais , Relação Dose-Resposta a Droga , Ouro/metabolismo , Masculino , Mitocôndrias Hepáticas/metabolismo , Mitocôndrias Hepáticas/patologia , Consumo de Oxigênio/fisiologia , Ratos , Ratos Wistar
9.
Acta Med Port ; 24(3): 475-80, 2011.
Artigo em Português | MEDLINE | ID: mdl-22015038

RESUMO

Subdural empyema is a life-threatening infection that may complicate acute sinusitis. The authors report the case of a previously healthy 10 year-old girl who presented with subdural empyema due to Gemella morbillorum after an untreated maxillary, ethmoidal and esphenoidal sinusitis. Despite immediate drainage of the empyema and underlying primary infection and treatment with broad spectrum antibiotics, she later developed frontal cerebritis and refractory intracranial hypertension, needing urgent decompressive craniectomy. She recovered gradually, maintaining to date slight right hemyparesis and aphasia. Even though it is considered a low virulence organism, G. morbillorum has been increasingly described in central nervous system infection. In this case, the prompt institution of broad spectrum antibiotics and surgical drainage, as well as the agressive treatment of complications, including decompressive craniectomy, were crucial to the patient's recovery.


Assuntos
Encefalopatias/complicações , Encefalopatias/microbiologia , Empiema Subdural/microbiologia , Gemella , Infecções por Bactérias Gram-Positivas/complicações , Sinusite/complicações , Sinusite/microbiologia , Doença Aguda , Criança , Feminino , Humanos
10.
Rev Port Pneumol ; 16(2): 287-305, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20437005

RESUMO

The past few years have seen a decline in community acquired pneumonia (CAP) in children in the western world, although this has gone hand-in-hand with more serious cases needing hospital admission. Our study characterises cases of CAP admitted to hospital and compares this data with a 2001 study. We collected data on 63 admissions over a six-month period. The majority were aged 0-2 years old. Chest X-ray showed consolidation/atelectasy in 58 (92.1%) and pleural effusion (PE) in 17 (27.0%), of which 11 were empyema (17.4% of all admissions). The bacterial agent was isolated in five cases: Streptococcus pyogenes (two, pleural fluid), Streptococcus pneumoniae (two, blood culture) and Haemophilus influenzae (one, blood culture). Sixty-one children (96.8%) were prescribed antibiotherapy. The median length of hospital stay was five days. Patients with PE were older, had a longer course of fever, higher inflammatory parameters, longer hospital stay and longer course of iv antibiotics. Compared to the prior study we found greater severity of CAP, with higher prevalence of PE and empyema. Nevertheless there was a shorter course of fever during hospital stay and shorter hospital stay. We also noticed less antibiotic prescription prior to admission and greater prescription of ampicillin during hospital stay. In the literature, the higher severity of CAP has been partially attributed to the emergence of more aggressive serotypes of Stretococcus pneumoniae not included in the heptavalent vaccine. There is therefore a greater interest in new vaccines containing them. Complicated CAP should be referred to centres specialising in its diagnosis and management.


Assuntos
Admissão do Paciente , Pneumonia Bacteriana , Criança , Pré-Escolar , Infecções Comunitárias Adquiridas/diagnóstico , Infecções Comunitárias Adquiridas/tratamento farmacológico , Infecções Comunitárias Adquiridas/epidemiologia , Estudos Transversais , Feminino , Humanos , Lactente , Masculino , Pneumonia Bacteriana/diagnóstico , Pneumonia Bacteriana/tratamento farmacológico , Pneumonia Bacteriana/epidemiologia , Estudos Retrospectivos , Fatores de Tempo
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