84 research outputs found
Viable stretchable plasmonics based on unidirectional nanoprisms
Well-defined ordered arrays of plasmonic nanostructures were fabricated on stretchable substrates and tunable plasmon-coupling-based sensing properties were comprehensively demonstrated upon extension and contraction. Regular nanoprism patterns consisting of Ag, Au and Ag/Au bilayers were constructed on the stretchable polydimethylsiloxane substrate. The nanoprisms had the same orientation over the entire substrate (3 x 3 cm(2)) via metal deposition on a single-crystal microparticle monolayer assembly. The plasmonic sensor based on the Ag/Au bilayer showed a 6-fold enhanced surface enhanced Raman scattering signal under 20% uniaxial extension, whereas a 3-fold increase was observed upon 6% contraction, compared with the Au nanoprism arrays. The sensory behaviors were corroborated by finite-difference time-domain simulation, demonstrating the tunable electromagnetic field enhancement effect via the localized surface plasmon resonance coupling. The advanced flexible plasmonic-coupling-based devices with tunable and quantifiable performance herein suggested are expected to unlock promising potential in practical bio-sensing, biotechnological applications and optical devices.11Ysciescopu
Targeting liver stage malaria with metformin
Copyright: © 2019, American Society for Clinical InvestigationDespite an unprecedented 2 decades of success, the combat against malaria - the mosquito-transmitted disease caused by Plasmodium parasites - is no longer progressing. Efforts toward eradication are threatened by the lack of an effective vaccine and a rise in antiparasite drug resistance. Alternative approaches are urgently needed. Repurposing of available, approved drugs with distinct modes of action are being considered as viable and immediate adjuncts to standard antimicrobial treatment. Such strategies may be well suited to the obligatory and clinically silent first phase of Plasmodium infection, where massive parasite replication occurs within hepatocytes in the liver. Here, we report that the widely used antidiabetic drug, metformin, impairs parasite liver stage development of both rodent-infecting Plasmodium berghei and human-infecting P. falciparum parasites. Prophylactic treatment with metformin curtails parasite intracellular growth in vitro. An additional effect was observed in mice with a decrease in the numbers of infected hepatocytes. Moreover, metformin provided in combination with conventional liver- or blood-acting antimalarial drugs further reduced the total burden of P. berghei infection and substantially lessened disease severity in mice. Together, our findings indicate that repurposing of metformin in a prophylactic regimen could be considered for malaria chemoprevention.This work was supported by Fundação para a Ciência e Tecnologia (Portugal) PTDC/SAU-MET/118199/2010 to LMS and European Research Council Proof of Concept Grant to MMM (ERC-2015-PoC-DL3–713691-REUSE4MALARIA).info:eu-repo/semantics/publishedVersio
Diagnóstico de enfermería “deterioro de la deambulación” en el anciano: revisión integradora de la literatura
The impaired walking nursing diagnosis has been included in NANDA International classification taxonomy in 1998, and this review aims to identify the defining characteristics and related factors in elderly patients in recent literature. Integrative literature review based on the following guiding question: Are there more defining characteristics and factors related to the nursing diagnosis impaired walking than those included in NANDA International classification taxonomy in elderly patients? Search conducted in 2007-2013 on international and Portuguese databases. Sample composed of 15 papers. Among the 6 defining characteristics classified at NANDA International, 3 were identified in the search results, but 13 were not included in the classification. Regarding the 14 related factors that are classified, 9 were identified in the sample and 12 were not included in the NANDA International taxonomy. This review allowed the identification of new elements not included in NANDA International Taxonomy and may contribute to the development of taxonomy and nursing knowledge.O diagnóstico de enfermagem deambulação prejudicada integra a NANDA Internacional desde 1998, e o objetivo deste estudo é identificar as características definidoras e os fatores relacionados no paciente idoso na literatura mais atual. Revisão integrativa com a questão: existirão mais características definidoras e fatores relacionados do diagnóstico de enfermagem deambulação prejudicada, além dos que estão descritos na NANDA Internacional, que sejam específicos para o paciente idoso? Pesquisa no período 2007-2013 em bases de dados internacionais e portuguesa. Obteve-se uma amostra de 15 estudos. Entre as 6 características definidoras do diagnóstico na classificação, 3 foram identificadas nos resultados da busca na literatura, contudo, encontram-se outras 13 que não constam da classificação. Relativamente aos fatores relacionados, dos 14 classificados, 9 foram identificados na amostra e 12 não estão na classificação. Essa revisão permitiu identificar novos elementos que não estão classificados na NANDA Internacional e pode contribuir para o desenvolvimento da taxonomia e do conhecimento de enfermagem.El diagnóstico de enfermería deterioro de la deambulación integra la NANDA Internacional desde 1998 y esta revisión tuvo como ob- jetivo identificar las características definidoras y los factores relacionados con el paciente anciano en la literatura más actual. Revisión integrada que surgió de la pregunta: ¿existirán más características y factores relacionados de deterioro de la deambulación, además de aquellas que están descritas en la NANDA Internacional, en el paciente anciano? Búsqueda en el período 2007-2013 en las bases de datos internacionales y portuguesa. Se obtuvo una muestra de 15 estudios. Entre las 6 características de diagnóstico en la clasificación, 3 fueron identificadas 3 en los resultados de la búsqueda, pero, otras 13 no constan en la NANDA Internacional. Con relación a los factores relacionados, 9 en la muestra y 12 no están en la clasificación. Nuevos elementos fueran identificados y no están clasificadas en la NANDA Internacional, ofreciendo así aportaciones para el desarrollo de la taxonomía y del conocimiento en enfermería.info:eu-repo/semantics/publishedVersio
Direct deposition of anatase TiO2 on thermally unstable gold nanobipyramid: Morphology-conserved plasmonic nanohybrid for combinational photothermal and photocatalytic cancer therapy
Deposition of crystalline titanium dioxide (TiO2) on gold nanostructures has been considered as a promising strategy for near-infrared (NIR) light-activated photocatalysis. A typical route comprises pre-deposition of amorphous TiO2 on the gold surface and its ensuing crystallization by high-temperature annealing. Such condition, however, is not compatible with highly plasmonic but thermally unstable sharp-tipped gold nanostructures, causing structural disruption and plasmonic decline. Herein, we report a hybridization method excluding high-temperature annealing, i.e., direct deposition of anatase TiO2 onto sharp-tipped gold nanobipyramid (Au NBP/a-TiO2) with conserving their morphology without agglomeration via low-temperature hydrothermal reaction. In addition to keeping the plasmonic photothermal performance, Au NBP/a-TiO2 exhibits enhanced photocatalytic generation of reactive oxygen species in response to the NIR excitation, evidencing the efficient injection of hot electrons from the Au NBP to the anatase shell. In vitro and in vivo studies revealed that the efficient photocatalytic/photothermal responses of Au NBP/a-TiO2, along with dispersion stability in biological media and minimal toxicity, hold potential for synergistic photothermal and photodynamic therapy. We believe that the low-temperature synthetic method introduced here might offer a general way of crystalline deposition of TiO2 on a variety of gold nanostructures, broadening the spectrum of NIR-responsive photocatalytic hybrid nanostructures for biomedical applications
Preclinical pharmacokinetics and biodistribution of anticancer dinuclear Palladium(II)-Spermine Complex (Pd2Spm) in mice
Palladium-based compounds are regarded as potential analogs to platinum anticancer drugs with improved properties. The present study assessed the pharmacokinetics and biodistribution of a dinuclear palladium(II)-spermine chelate (Pd2Spm), which has previously been shown to possess promising in vitro activity against several therapy-resistant cancers. Using inductively coupled plasma-mass spectrometry, the kinetic profiles of palladium/platinum in serum, serum ultrafiltrate and tissues (kidney, liver, brain, heart, lungs, ovaries, adipose tissue and mammary glands) were studied in healthy female Balb/c mice after a single intraperitoneal bolus injection of Pd2Spm (3 mg/kg bw) or cisplatin (3.5 mg/kg bw) between 0.5 and 48 h post-injection. Palladium in serum exhibited biphasic kinetics with a terminal half-life of 20.7 h, while the free palladium in serum ultrafiltrate showed a higher terminal half-life than platinum (35.5 versus 31.5 h). Palladium was distributed throughout most of the tissues except for the brain, with the highest values in the kidney, followed by the liver, lungs, ovaries, adipose tissue and mammary glands. The in vitro cellular accumulation was also evaluated in breast cancer cells, evidencing a passive diffusion as a mechanism of Pd2Spm’s cellular entry. This study reports, for the first time, the favorable pharmacokinetics and biodistribution of Pd2Spm, which may become a promising pharmacological agent for cancer treatmentinfo:eu-repo/semantics/publishedVersio
Monitoring Antibiotic Comsumption in the Surgery and Orthopaedics
A monitorização do consumo de antimicrobianos é um instrumento de interesse indiscutível e tem merecido uma atenção particular nos últimos anos, devido às crescentes preocupações com a emergência de estirpes microbianas multi-resistentes.
Os objectivos do presente estudo consistiram, por um lado, na monitorização do consumo e na avaliação do impacto económico da prescrição hospitalar de antimicrobianos, em serviços de cirurgia
e ortopedia. Por outro lado, pretendeu-se estudar e a relação indicação-prescrição terapêutica e profilática.
Tendo presentes estes objectivos realizou-se um estudo-piloto longitudinal, com recolha de dados durante o mês de Maio de 2004, em seis Hospitais SA, incidindo numa amostra total de 1.122 doentes internados.
Verificámos uma taxa de incidência de prescrição de 76,9%, com dispensa de 1.154 antimicrobianos, dos quais 71,2% se destinaram, em média, à profilaxia da infecção pós-cirúrgica, atestando a adesão
geral à prática da profilaxia da infecção no local cirúrgico.
O custo médio da antibioterapia foi mais elevado nos casos de “suspeita de infecção” (€9,09) ou “infecção declarada” (€8,74) e mais baixo quando utilizados para “profilaxia” (€5,67), facto relacionado
com a menor duração média dos episódios de profilaxia.
Os regimes de profilaxia utilizados apresentaram variações consideráveis entre os diferentes hospitais no que respeita ao tipo de antibiótico utilizado e uma duração média de 2,61 dias, com cerca de metade dos episódios de profilaxia prolongando-se por mais de 24 horas, sugerindo uma implementação
insuficiente das actuais recomendações quanto ao tipo de fármaco a utilizar para esta prática, o que aponta para o necessidade duma avaliação da existência nas unidades hospitalares, de recomendações
claras para a profilaxia da infecção do local cirúrgico, bem como da adesão dos clínicos a estas
Pd2Spermine Complex Shows Cancer Selectivity and Efficacy to Inhibit Growth of Triple-Negative Breast Tumors in Mice
Pd2Spm is a dinuclear palladium(II)-spermine chelate with promising anticancer properties against triple-negative breast cancer (TNBC), a breast carcinoma subset with poor prognosis and limited treatment options. The present study evaluated the in vitro and in vivo anticancer effects of Pd2Spm compared to the reference metal-based drug cisplatin. Triple-negative breast cancer MDA-MB-231 cells, non-cancerous MCF-12A breast cells and chorioallantoic membrane (CAM) assay were used for antiproliferative, antimigratory and antiangiogenic studies. For an in vivo efficacy study, female CBA nude mice with subcutaneously implanted MDA-MB-231 breast tumors were treated with Pd2Spm (5 mg/kg/day) or cisplatin (2 mg/kg/day) administered intraperitoneally during 5 consecutive days. Promising selective antiproliferative activity of Pd2Spm was observed in MDA-MB-231 cells (IC50 values of 7.3-8.3 µM), with at least 10-fold lower activity in MCF-12A cells (IC50 values of 89.5-228.9 µM). Pd2Spm inhibited the migration of MDA-MB-231 cells, suppressed angiogenesis in CAM and decreased VEGF secretion from MDA-MB-231 cells with similar potency as cisplatin. Pd2Spm-treated mice showed a significant reduction in tumor growth progression, and tumors evidenced a reduction in the Ki-67 proliferation index and number of mitotic figures, as well as increased DNA damage, similar to cisplatin-treated animals. Encouragingly, systemic toxicity (hematotoxicity and weight loss) observed in cisplatin-treated animals was not observed in Pd2Spm-treated mice. The present study reports, for the first time, promising cancer selectivity, in vivo antitumor activity towards TNBC and a low systemic toxicity of Pd2Spm. Thus, this agent may be viewed as a promising Pd(II) drug candidate for the treatment of this type of low-prognosis neoplasia
Investigating the role of symptom valorisation in tuberculosis patient delay in urban areas in Portugal
URBANTB group: Patrícia Soares (Representative of the consortium), Mário Carreira, Sofia Pereira, Catarina Alves, Filipe Alves, Ana Rodrigues, Ana Moreira, Márcia Cardoso, Sandra Mota, Ana Gomes, Liliana Ferreira, Marta Lopes, Isabel Correia, Juan Rachadell, Maria Gameiro, Ângela Dias, Manuel Pereira, Jorge Gonçalves, Maria Gonçalves, Adriana Taveira, Celene Neves, Lucinda Silva, Maria Mendes, Maria Teixeira, Maria Pereira, Milena Piedade, Antónia Teixeira & Carlos Carvalho.Background: Diagnosis delay contributes to increased tuberculosis (TB) transmission and morbimortality. TB incidence has been decreasing in Portugal, but median patient delay (PD) has risen. Symptom valorisation may determine PD by influencing help-seeking behaviour. We aimed to analyse the association between symptom valorisation and PD, while characterising individuals who disregarded their symptoms.
Methods: A cross-sectional study was conducted among TB patients in Lisbon and Oporto in 2019 - 2021. Subjects who delayed seeking care because they did not value their symptoms or thought these would go away on their own were considered to have disregarded their symptoms. PD was categorised using a 21-day cut-off, and a 30-day cut-off for sensitivity analysis. We estimated the effect of symptom valorisation on PD through a directed acyclic graph. Then, a multivariable regression analysis characterised patients that disregarded their symptoms, adjusting for relevant variables. We fitted Poisson regression models to estimate crude and adjusted prevalence ratios (PR).
Results: The study included 75 patients. Median PD was 25 days (IQR 11.5-63.5), and 56.0% of participants had PD exceeding 21 days. Symptom disregard was reported by 38.7% of patients. Patients who did not value their symptoms had higher prevalence of PD exceeding 21 days compared to those who valued their symptoms [PR 1.59 (95% CI 1.05-2.42)]. The sensitivity analysis showed consistent point estimates but wider confidence intervals [PR 1.39 (95% CI 0.77-2.55)]. Being a smoker was a risk factor for symptom disregard [PR 2.35 (95% CI 1.14-4.82)], while living in Oporto [PR 0.35 (95% CI 0.16-0.75)] and having higher household incomes [PR 0.39 (95% CI 0.17-0.94)] were protective factors.
Conclusions: These findings emphasise the importance of symptom valorisation in timely TB diagnosis. Patients who did not value their symptoms had longer PD, indicating a need for interventions to improve symptom recognition. Our findings also corroborate the importance of the socioeconomic determinants of health, highlighting tobacco as a risk factor both for TB and for PD.This work was supported by the Fundação para a Ciência e Tecnologia (FCT, Portugal) [Grant: PTDC/SAU-PUB/31346/2017]. The present publication was funded by Fundação para a Ciência e Tecnologia (FCT, Portugal) national support through Comprehensive Health Research Centre (CHRC) [UIDP/04923/2020].info:eu-repo/semantics/publishedVersio
Influenza severe cases in hospitals, between 2014 and 2016 in Portugal
Rede Portuguesa de Laboratórios para o Diagnóstico da GripeBackground: Since 2009, the Portuguese Laboratory Network (PLNID) for Influenza Diagnosis has integrated 15 Laboratories in mainland and Atlantic Islands of Azores and Madeira. This PLNID added an important contribute to the National Influenza Surveillance Program regarding severe and hospitalized influenza cases. The present study aims to describe influenza viruses detected in influenza like illness (ILI) cases: outpatients (Outp), hospitalized (Hosp), and intensive care units (ICU), between 2014 and 2016.
Methods: The PLNID performs influenza virus diagnosis by biomolecular methodologies. Weekly reports to the National Influenza Reference Laboratory ILI cases tested for influenza. Reports include data on detecting viruses, hospital assistance, antiviral therapeutics, and information on death outcome. Were reported during two winter seasons 8059 ILI cases,being 3560 cases in 2014/15 (1024 in Outp, 1750 Hosp, and 606 in ICU) and 4499 cases in 2015/2016 (1933 in Outp, 1826 Hosp, and 740 in ICU).
Results: The higher percentage of influenza positive cases were detected in Outp in both seasons, 18% during 2014/15 and 20% in 2015/16. In 2014/15,influenza cases were more frequent in individuals older than 65 years old and these required more hospitalizations,even in ICU. In 2015/16,the influenza cases were mainly detected in individuals between 15-64 years old. A higher proportion of influenza positive cases with hospitalization in ICU were observed in adults between 45-64 years old.During the study period,the predominant circulating influenza viruses were different in the two seasons: influenza B and A(H3) co-circulated in 2014/15,and influenza A(H1)pdm09 was predominant during 2015/16. Even when influenza A is notthe dominant virus, A(H3) and A(H1)pdm09 subtypes correlate with higher detection rate in hospitalized cases (Hosp and UCI), with higher frequencies in adults older than 45. Influenza B,detected in higher proportion in outpatients, was frequently relatedwith influenza cases in younger age groups: 0-4 and 5-14 years old.
Conclusions: This study highlights the correlation of theinfluenza virus type/subtype that circulates in each season with the possible need for hospitalization and intensive care in special groups of the population. Circulation of influenza A subtypes can cause more frequentdisease in individuals older than 45, with need of hospitalization including intensive care. On the other hand, influenza B is more frequently associated with less severe cases and with infection in children and younger adults. Influenza B circulation might predict lower number of hospitalizations.The identification of influenza type in circulation,byPLNID ineach season, could guide action planning measures in population health care.info:eu-repo/semantics/publishedVersio
Lettuce and marigold intercropping: crops productivity and marigold's flavonoid content
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