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1.
Biofouling ; 39(2): 204-217, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-37092276

RESUMO

Removing lampenflora, phototrophic organisms developing on rock surfaces in tourist cavities due to the artificial lighting, is a challenge for sustainable and appropriate long-term management of caves. Photosynthetic-based biofilms usually cause rock biodeterioration and an ecological imbalance in cave ecosystems. In this work, a detailed investigation of the effects of the 3 most commonly used lampenflora cleaning operations (NaClO, H2O2 and UVC) was carried out in Pertosa-Auletta Cave (Italy). The application of NaClO showed good disinfection capability over extended periods of time without causing any appreciable rock deterioration. The H2O2 treatment showed to be corrosive for the rock surfaces covered with vermiculation deposits. The chemical alteration of organic and inorganic compounds by H2O2 did not remove biomass, favoring biofilm recovery after three months of treatment. Both NaClO and H2O2 treatments were effective at removing photoautotrophs, although the bacterial phyla Proteobacteria and Bacteroidetes as well as Apicomplexa and Cercozoa among the Eukaryotes, were found to be resistant to these treatments. The UVC treatments did not show any noticeable effect on the biofilms.


Assuntos
Ecossistema , Peróxido de Hidrogênio , Biofilmes , Bactérias , Fotossíntese
2.
Molecules ; 28(19)2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37836666

RESUMO

Fluorescent labels are key tools in a wide range of modern scientific applications, such as fluorescence microscopy, flow cytometry, histochemistry, direct and indirect immunochemistry, and fluorescence in situ hybridization (FISH). Small fluorescent labels have important practical advantages as they allow maximizing the fluorescence signal by binding multiple fluorophores to a single biomolecule. At present, the most widely used fluorescent labels available present small Stokes shifts and are too costly to be used in routine applications. In this work we present four new coumarin derivatives, as promising and inexpensive fluorescent labels for biomolecules, obtained through a cost-effective, efficient, and straightforward synthetic strategy. Density functional theory and time-dependent density functional theory calculations of the electronic ground and lowest-lying singlet excited states were carried out in order to gain insights into the observed photophysical properties.


Assuntos
Corantes Fluorescentes , Hibridização in Situ Fluorescente , Análise Custo-Benefício , Corantes Fluorescentes/química
3.
Rev Esp Enferm Dig ; 115(3): 151, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36043539

RESUMO

The use of lumen-apposing metal stent is well defined for endoscopic ultrasound-guided drainage of pancreatic collections (e.g. WON). However, it is not yet a well-established approach in the management of postsurgical collections. We present an alternative application of LAMS for EUS drainage of pelvic abscess, showing that it is a safe and minimally invasive technique, with excellent clinical results. This technique should be considered as a drainage alternative in these scenarios due to its lower morbidity and mortality, opening a new era in the approach to these lesions.


Assuntos
Abscesso Abdominal , Abscesso , Humanos , Abscesso/diagnóstico por imagem , Abscesso/cirurgia , Resultado do Tratamento , Stents , Endossonografia , Drenagem/métodos , Ultrassonografia de Intervenção
4.
Molecules ; 27(5)2022 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-35268562

RESUMO

Important scientific areas, such as cellular biology, medicine, pharmacy, and environmental sciences, are dependent on very sensitive analytical techniques to track and detect biomolecules. In this work, we develop a simple, low-cost and effective synthetic strategy to produce new red-shifted 4-styrylcoumarin derivatives as promising inexpensive fluorescent labels for biomolecules. The extension of the delocalized π-electron system results in bathochromic shifts in these new coumarin derivatives, which also present large Stokes shifts. In addition, density functional theory and time-dependent density functional theory calculations helped to rationalize the photophysical properties observed by the experimental results.


Assuntos
Cumarínicos
5.
Rev Esp Enferm Dig ; 113(8): 563-569, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33267594

RESUMO

INTRODUCTION: hepatic osteodystrophy, including osteoporosis, is an abnormal bone metabolism related with chronic liver diseases. Osteoporosis is associated with an increased risk of bone fractures, with a significant impact on morbidity, mortality and healthcare costs. Nevertheless, bone disorders tend to be undervalued in cirrhosis due to alcohol-related liver disease (ALD cirrhosis). This study aimed to assess the prevalence of hepatic osteodystrophy and osteoporosis in ALD cirrhosis. METHODS: a prospective observational study was performed that included patients with ALD cirrhosis, between September 2017 and December 2018. Bone mineral density was determined by dual energy X-ray absorptiometry at the lumbar spine and the femoral neck. Hepatic osteodystrophy was defined as a T-score below -1 SD and osteoporosis as a T-score below -2.5 SD. RESULTS: ninety-four patients were included; 24.5 % (n = 23) had prior fragility fractures and ten patients suffered new osteoporotic fractures during the study period. Hepatic osteodystrophy was diagnosed in 79.8 % (n = 75) and osteoporosis in 21.3 % (n = 20) of cases. Patients with hepatic osteodystrophy presented significantly worse Child-Turcotte-Pugh (p < 0.05) and Model for End-Stage Liver Disease (MELD-sodium) scores (p = 0.01). According to the multivariate analysis, lower body mass index (BMI) (OR = 0.787, 95 % CI: 0.688-0.901, p = 0.001) and vitamin D deficiency (OR = 6.798, 95 % CI: 1.775-26.038, p = 0.005) were significantly and independently associated with hepatic osteodystrophy. Patients with osteoporosis also had a lower BMI (p = 0.01). Female patients and those with prior fragility fractures were more likely to suffer from osteoporosis (p < 0.05). CONCLUSION: our study revealed a high prevalence of hepatic osteodystrophy and osteoporosis in patients with ALD cirrhosis (particularly in those with a lower BMI) and a concerning high rate of fragility fractures. Bone mineral density should be assessed in order to allow for an early diagnosis and the implementation of preventive measures.


Assuntos
Doença Hepática Terminal , Hepatopatias , Absorciometria de Fóton , Densidade Óssea , Feminino , Humanos , Cirrose Hepática/complicações , Cirrose Hepática/epidemiologia , Fatores de Risco , Índice de Gravidade de Doença
6.
Rev Esp Enferm Dig ; 111(3): 248, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30449113

RESUMO

Acute ischemia of the gastric mucosa, resulting in a black stomach, is a very rare event given the blood supply of the stomach, with a rich collateral blood flow system. We present the case of a 65-year-old man, with polycythemia of unknown origin under investigation, presented to the emergency department with a history of diffuse abdominal pain and hematemesis. Blood tests revealed a hemoglobin level of 22 g/dL.Upper endoscopy revealed a black ulcerated gastric mucosa compatible with acute necrosis of the corpus and antrum of the stomach . Despite few cases described in the literature, many etiologic factors have been suggested. In this particular case, given the severe polycythemia and associated hyperviscosity, vascular compromise of the gastric blood vessels might have played a major role in the pathogenesis of the ischemic process.


Assuntos
Mucosa Gástrica/irrigação sanguínea , Isquemia/etiologia , Policitemia/complicações , Estômago/patologia , Idoso , Mucosa Gástrica/patologia , Humanos , Masculino , Necrose/patologia , Estômago/irrigação sanguínea
8.
Rev Esp Enferm Dig ; 109(8): 596, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28625069

RESUMO

With this report we alert to an extremely rare case of duodenal metastases, from an endometrial adenocarcinoma by lymphatic spread and whose primary manifestation was with gastrointestinal bleeding. We think this is the first case reported of duodenal metastases from endometrial carcinoma and with this presentation.


Assuntos
Adenocarcinoma/secundário , Neoplasias Duodenais/complicações , Neoplasias Duodenais/secundário , Neoplasias do Endométrio/patologia , Hemorragia Gastrointestinal/etiologia , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/patologia , Idoso , Neoplasias Duodenais/diagnóstico por imagem , Neoplasias do Endométrio/diagnóstico por imagem , Endoscopia do Sistema Digestório , Feminino , Hemorragia Gastrointestinal/diagnóstico por imagem , Humanos , Tomografia Computadorizada por Raios X
10.
Microsc Microanal ; 21(1): 78-83, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25358672

RESUMO

Mural paintings are some of the oldest and most important cultural expressions of mankind and play an important role for the understanding of societies and civilizations. These cultural assets have high economic and cultural value and therefore their degradation has social and economic impact. The present work presents a novel microanalytical approach to understand the damages caused by microbial communities in mural paintings. This comprises the characterization and identification of microbial diversity and evaluation of damage promoted by their biological activity. Culture-dependent methods and DNA-based approaches like denaturing gradient gel electrophoresis (DGGE) and pyrosequencing are important tools in the isolation and identification of the microbial communities allowing characterization of the biota involved in the biodeterioration phenomena. Raman microspectrometry, infrared spectrometry, and variable pressure scanning electron microscopy coupled with energy-dispersive X-ray spectrometry are also useful tools for evaluation of the presence of microbial contamination and detection of the alteration products resulting from metabolic activity of the microorganisms. This study shows that the degradation status of mural paintings can be correlated to the presence of metabolically active microorganisms.


Assuntos
Bactérias/isolamento & purificação , Biodiversidade , Fungos/isolamento & purificação , Pinturas , Bactérias/classificação , Bactérias/genética , Bactérias/ultraestrutura , Fungos/classificação , Fungos/genética , Fungos/ultraestrutura , Microscopia Eletrônica de Varredura
11.
Microsc Microanal ; 21(1): 63-77, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25787782

RESUMO

This work comprises the use of a multi-analytical approach combined with microbiological studies to characterize six paper samples, containing foxing stains, from the 20th century, regarding their cellulose matrix, fillers, and sizing materials, and to evaluate possible paper degradation that might have occurred during the foxing stains. Photography under different illuminations and optical microscopy were used for morphological characterization of the paper samples and foxing stains. Scanning electron microscopy coupled energy dispersive spectroscopy (SEM-EDS) was of particular importance for defining the presence of fiber disorder and disruption on the surface of some of the stains, and localized accumulations of mineral-like particles on the surface of others. SEM-EDS, attenuated total reflection Fourier transform infrared spectroscopy (ATR-FT-IR), and energy dispersive X-ray fluorescence (EDXRF) were used for the identification of mineral fillers, whereas sizing agents were analyzed using ATR-FT-IR. EDXRF results showed that no differences, within the standard deviation, were found in iron and copper contents between the foxed and unfoxed areas. Fungi belonging to the genus Penicillium spp. were found in all the paper samples. Unfoxed areas presented lower contamination than the foxed areas.


Assuntos
Bactérias/isolamento & purificação , Corantes/análise , Fungos/isolamento & purificação , Papel/história , Bactérias/genética , Corantes/história , Fungos/genética , História do Século XX , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier
12.
Microsc Microanal ; 21(1): 2-14, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25389801

RESUMO

A 16th century liturgical cope belonging to D. Teotónio of Braganza (collection of the Museum of Évora, ME 172/1) was selected for a material study. The cope is made of a variety of materials that include two different types of metal threads, dyed silk yarns, and vegetable yarns used in the weft. Several samples from different points representing the different metal thread types and colored silk yarns were collected. Stereomicroscopy (optical microscopy) and scanning electron microscopy were used for morphological analysis of the textile fibers and evaluation of metal thread degradation products. Evaluation of mordants and metal thread composition was carried out by energy-dispersive X-ray spectroscopy. Liquid chromatography with diode array and mass spectrometry detection was used for dye identification, which allowed the determination of three different red dye sources and one yellow dye source in the colored silk yarns. Although different fabrics were used in the manufacturing of the cope, similarities identified in the characterization of the materials suggest that a single workshop was involved in its making.

15.
Sci Rep ; 14(1): 3131, 2024 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-38326517

RESUMO

The coronavirus disease 2019 (COVID-19) has infected many institutionalised elderly people. In Portugal, the level of pandemic fear among professional caregivers of the elderly is unknown, as are its predictive factors. This study aimed to investigate predictors of fear of COVID-19 among workers caring for institutionalised elderly people in nursing homes. This is a cross-sectional study using multiple linear regression applied to a population of 652 caregivers located in 14 municipalities in Central Alentejo, Portugal, at March 2021. The criterion variable was the fear of COVID-19. Standardised regression coefficients showed that the higher the level of education, the lower the level of fear (ß = - 0.158; t = - 4.134; p < .001). Other predictors of the level of fear were gender, with women having higher levels (ß = 0.123; t = t = 3.203; p < 0.001), higher scores on COVID-19-like suspicious symptoms (ß = 0.123; t = 3.219; p < 0.001) and having received a flu vaccine (ß = 0.086; t = 2.252; p = 0.025). The model explains 6.7% of the variation in fear of COVID-19 (R2Adj = 0.067). Health literacy can minimise the impact on the physical and mental health of these workers. In Central Alentejo, caregivers of the elderly play a fundamental role in social balance. Further studies are needed to better understand the factors that can improve their personal and professional well-being.


Assuntos
COVID-19 , Humanos , Feminino , Idoso , COVID-19/epidemiologia , Cuidadores/psicologia , Estudos Transversais , Portugal/epidemiologia , Medo/psicologia
16.
Microorganisms ; 12(6)2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38930597

RESUMO

Microbial contamination poses a threat to both the preservation of library and archival collections and the health of staff and users. This study investigated the microbial communities and potential health risks associated with the UNESCO-classified Norwegian Sea Trade Archive (NST Archive) collection exhibiting visible microbial colonization and staff health concerns. Dust samples from book surfaces and the storage environment were analysed using culturing methods, qPCR, Next Generation Sequencing, and mycotoxin, cytotoxicity, and azole resistance assays. Penicillium sp., Aspergillus sp., and Cladosporium sp. were the most common fungi identified, with some potentially toxic species like Stachybotrys sp., Toxicladosporium sp., and Aspergillus section Fumigati. Fungal resistance to azoles was not detected. Only one mycotoxin, sterigmatocystin, was found in a heavily contaminated book. Dust extracts from books exhibited moderate to high cytotoxicity on human lung cells, suggesting a potential respiratory risk. The collection had higher contamination levels compared to the storage environment, likely due to improved storage conditions. Even though overall low contamination levels were obtained, these might be underestimated due to the presence of salt (from cod preservation) that could have interfered with the analyses. This study underlines the importance of monitoring microbial communities and implementing proper storage measures to safeguard cultural heritage and staff well-being.

17.
Sci Total Environ ; 913: 169583, 2024 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-38154629

RESUMO

Lanzarote (Canary Islands, Spain) is one of the best terrestrial analogs to Martian volcanology. Particularly, Lanzarote lava tubes may offer access to recognizably preserved chemical and morphological biosignatures valuable for astrobiology. By combining microbiological, mineralogical, and organic geochemistry tools, an in-depth characterization of speleothems and associated microbial communities in lava tubes of Lanzarote is provided. The aim is to untangle the underlying factors influencing microbial colonization in Earth's subsurface to gain insight into the possibility of similar subsurface microbial habitats on Mars and to identify biosignatures preserved in lava tubes unequivocally. The microbial communities with relevant representativeness comprise chemoorganotrophic, halophiles, and/or halotolerant bacteria that have evolved as a result of the surrounding oceanic environmental conditions. Many of these bacteria have a fundamental role in reshaping cave deposits due to their carbonatogenic ability, leaving behind an organic record that can provide evidence of past or present life. Based on functional profiling, we infer that Crossiella is involved in fluorapatite precipitation via urea hydrolysis and propose its Ca-rich precipitates as compelling biosignatures valuable for astrobiology. In this sense, analytical pyrolysis, stable isotope analysis, and chemometrics were conducted to characterize the complex organic fraction preserved in the speleothems and find relationships among organic families, microbial taxa, and precipitated minerals. We relate organic compounds with subsurface microbial taxa, showing that organic families drive the microbiota of Lanzarote lava tubes. Our data indicate that bacterial communities are important contributors to biomarker records in volcanic-hosted speleothems. Within them, the lipid fraction primarily consists of low molecular weight n-alkanes, α-alkenes, and branched-alkenes, providing further evidence that microorganisms serve as the origin of organic matter in these formations. The ongoing research in Lanzarote's lava tubes will help develop protocols, routines, and predictive models that could provide guidance on choosing locations and methodologies for searching potential biosignatures on Mars.


Assuntos
Marte , Microbiota , Humanos , Meio Ambiente Extraterreno , Minerais , Alcenos
18.
Bioorg Med Chem ; 21(7): 1911-7, 2013 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-23419323

RESUMO

The design and synthesis of a small library of pyrrolidine iminocyclitol inhibitors with a structural similarity to 1,4-dideoxy-1,4-imino-D-arabitol (DAB-1) is reported. This library was specifically designed to gain a better insight into the mechanism of inhibition of glycosidases by polyhydroxylated pyrrolidines or iminocyclitols. Pyrrolidine-3,4-diol 15a and pyrrolidine-3,4-diol diacetate 15b had emerged as the most potent α-glucosidase inhibitors in the series. Docking studies performed with an homology model of α-glucosidase disclosed binding poses for compounds 15a, 15b, 16a, and 16a' occupying the same region as the NH group of the terminal ring of acarbose and suggest a closer and stronger binding of compound 15a and 15b with the enzyme active site residues. Our studies indicate that 2 or 5-hydroxyl substituents appear to be vital for high inhibitory activity.


Assuntos
Ciclitóis/química , Ciclitóis/farmacologia , Inibidores de Glicosídeo Hidrolases , Pirrolidinas/química , Pirrolidinas/farmacologia , Saccharomyces cerevisiae/enzimologia , Ciclitóis/síntese química , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Simulação de Acoplamento Molecular , Ligação Proteica , Pirrolidinas/síntese química , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/efeitos dos fármacos , alfa-Glucosidases/química , alfa-Glucosidases/metabolismo
20.
Microorganisms ; 11(2)2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36838343

RESUMO

Nanoparticles (1 to 100 nm) have unique physical and chemical properties, which makes them suitable for application in a vast range of scientific and technological fields. In particular, metal nanoparticle (MNPs) research has been showing promising antimicrobial activities, paving the way for new applications. However, despite some research into their antimicrobial potential, the antimicrobial mechanisms are still not well determined. Nanoparticles' biosynthesis, using plant extracts or microorganisms, has shown promising results as green alternatives to chemical synthesis; however, the knowledge regarding the mechanisms behind it is neither abundant nor consensual. In this review, findings from studies on the antimicrobial and biosynthesis mechanisms of MNPs were compiled and evidence-based mechanisms proposed. The first revealed the importance of enzymatic disturbance by internalized metal ions, while the second illustrated the role of reducing and negatively charged molecules. Additionally, the main results from recent studies (2018-2022) on the biosynthesis of MNPs using microorganisms were summarized and analyzed, evidencing a prevalence of research on silver nanoparticles synthesized using bacteria aiming toward testing their antimicrobial potential. Finally, a synopsis of studies on MNPs applied to cultural heritage materials showed potential for their future use in preservation.

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