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1.
BMC Endocr Disord ; 24(1): 145, 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39123199

RESUMO

BACKGROUND: Viral respiratory infections may precipitate type 1 diabetes (T1D). A possible association between the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus responsible for COVID-19, and the incidence of T1D is being determined. This study was carried out using Portuguese registries, aiming at examining temporal trends between COVID-19 and T1D. METHODS: Hospital data, comparing the incidence before and during the COVID-19 pandemic, from children and young adults diagnosed with new-onset T1D, was acquired beginning in 2017 and until the end of 2022. Data was obtained from nine different Portuguese hospital units. The impact of the COVID-19 pandemic, beginning in March 2020, was assessed comparing the annual numbers of new-onset T1D cases. The annual median levels of glucose, glycated hemoglobin (HbA1c) and fasting C-peptide at T1D diagnosis were compared. The annual number of diabetic ketoacidosis (DKA) episodes among new T1D cases was also assessed at two centers. RESULTS: In total, data from 574 newly diagnosed T1D patients was analyzed, including 530 (92.3%) children. The mean ages for child and adult patients were 9.1 (SD 4.4) and 32.8 (SD 13.6) years, respectively. 57.8% (331/573) were male, one patient had unknown sex. The overall median (25-75 percentiles) levels of glucose, HbA1c and fasting C-peptide at diagnosis were 454 mg/dL (356-568), 11.8% (10.1-13.4) and 0.50 µg/L (0.30-0.79), respectively. DKA at T1D diagnosis was present in 48.4% (76/157). For eight centers with complete 2018 to 2021 data (all calendar months), no overall significant increase in T1D cases was observed during the COVID-19 pandemic, i.e. 90 cases in 2018, 90 cases in 2019, 112 in 2020 and 100 in 2021 (P for trend = 0.36). Two of the centers, Faro (CHUA) and Dona Estefânia (CHULC) hospitals, did however see an increase in T1D from 2019 to 2020. No significant changes in glucose (P = 0.32), HbA1c (P = 0.68), fasting C-peptide (P = 0.20) or DKA frequency (P = 0.68) at the time of T1D diagnosis were observed over the entire study period. CONCLUSION: The T1D incidence did not increase significantly, when comparing the years before and during the COVID-19 pandemic, nor did key metabolic parameters or number of DKA episodes change.


Assuntos
COVID-19 , Diabetes Mellitus Tipo 1 , Sistema de Registros , Humanos , COVID-19/epidemiologia , COVID-19/complicações , Diabetes Mellitus Tipo 1/epidemiologia , Diabetes Mellitus Tipo 1/complicações , Masculino , Portugal/epidemiologia , Feminino , Incidência , Criança , Adulto , Adolescente , Adulto Jovem , Pré-Escolar , Hemoglobinas Glicadas/análise , Hemoglobinas Glicadas/metabolismo , SARS-CoV-2 , Cetoacidose Diabética/epidemiologia , Glicemia/análise , Glicemia/metabolismo
2.
Int J Mol Sci ; 25(14)2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39063237

RESUMO

Increasing exposure to unfavorable temperatures and water deficit imposes major constraints on most crops worldwide. Despite several studies regarding coffee responses to abiotic stresses, transcriptome modulation due to simultaneous stresses remains poorly understood. This study unravels transcriptomic responses under the combined action of drought and temperature in leaves from the two most traded species: Coffea canephora cv. Conilon Clone 153 (CL153) and C. arabica cv. Icatu. Substantial transcriptomic changes were found, especially in response to the combination of stresses that cannot be explained by an additive effect. A large number of genes were involved in stress responses, with photosynthesis and other physiologically related genes usually being negatively affected. In both genotypes, genes encoding for protective proteins, such as dehydrins and heat shock proteins, were positively regulated. Transcription factors (TFs), including MADS-box genes, were down-regulated, although responses were genotype-dependent. In contrast to Icatu, only a few drought- and heat-responsive DEGs were recorded in CL153, which also reacted more significantly in terms of the number of DEGs and enriched GO terms, suggesting a high ability to cope with stresses. This research provides novel insights into the molecular mechanisms underlying leaf Coffea responses to drought and heat, revealing their influence on gene expression.


Assuntos
Coffea , Secas , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Temperatura Alta , Transcriptoma , Coffea/genética , Coffea/metabolismo , Estresse Fisiológico/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Folhas de Planta/genética , Folhas de Planta/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Genótipo
3.
Microb Ecol ; 85(4): 1215-1225, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-35415771

RESUMO

Anthropogenic change at a global scale is affecting life on Earth with impacts on freshwaters. Aquatic hyphomycetes are fungi that drive organic matter decomposition in freshwaters and mediate energy transfer to higher trophic levels. Intraspecific trait variability affects ecological processes and can account for species adaptations to environmental change. To ascertain how aquatic hyphomycetes respond to global change related stressors, we selected 20 strains (7 species), based on their co-occurrence in streams and phylogenetic relatedness. We measured fungal growth rates at different temperatures (7 levels), nutrient concentrations (6 levels) and medium moisture (6 levels). Our results indicate that all stressors affected fungal growth, and responses to nutrient enrichment and moisture were strain specific. Fungal responses to the stressors were not explained by their phylogenetic relatedness. In the absence of stressors, interspecific diversity best explained the variance in fungal traits, while the increase in the stress gradient increased the importance of intraspecific diversity.


Assuntos
Fungos Mitospóricos , Filogenia , Fungos Mitospóricos/fisiologia , Rios/microbiologia , Água Doce , Fenótipo , Folhas de Planta/microbiologia , Fungos/genética , Ecossistema
4.
Int J Mol Sci ; 24(4)2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36834624

RESUMO

Drought is a major constraint to plant growth and productivity worldwide and will aggravate as water availability becomes scarcer. Although elevated air [CO2] might mitigate some of these effects in plants, the mechanisms underlying the involved responses are poorly understood in woody economically important crops such as Coffea. This study analyzed transcriptome changes in Coffea canephora cv. CL153 and C. arabica cv. Icatu exposed to moderate (MWD) or severe water deficits (SWD) and grown under ambient (aCO2) or elevated (eCO2) air [CO2]. We found that changes in expression levels and regulatory pathways were barely affected by MWD, while the SWD condition led to a down-regulation of most differentially expressed genes (DEGs). eCO2 attenuated the impacts of drought in the transcripts of both genotypes but mostly in Icatu, in agreement with physiological and metabolic studies. A predominance of protective and reactive oxygen species (ROS)-scavenging-related genes, directly or indirectly associated with ABA signaling pathways, was found in Coffea responses, including genes involved in water deprivation and desiccation, such as protein phosphatases in Icatu, and aspartic proteases and dehydrins in CL153, whose expression was validated by qRT-PCR. The existence of a complex post-transcriptional regulatory mechanism appears to occur in Coffea explaining some apparent discrepancies between transcriptomic, proteomic, and physiological data in these genotypes.


Assuntos
Coffea , Coffea/genética , Espécies Reativas de Oxigênio/metabolismo , Dióxido de Carbono/metabolismo , Resistência à Seca , Proteômica , Café/genética , Secas , Água/metabolismo , Regulação da Expressão Gênica de Plantas
5.
Molecules ; 28(21)2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37959787

RESUMO

BACKGROUND: Grape agri-food wastes, such as skin, seeds, and other discarded by-products, contain phytochemical compounds that offer potential health benefits. METHODS: This study aimed to investigate the polyphenol composition and bioactivities of different extracts obtained from grape marc and seeds, with the goal of exploring their potential for application as natural food additives. RESULTS: Regardless of the extraction method used (dynamic maceration, ultrasound-assisted extraction (UAE), and microwave-assisted extraction (MAE)), all extracts exhibited relatively high concentrations of phenolic compounds. The chemical characterization of the extracts revealed the presence of specific compounds and chemical groups associated with each extraction methodology. Moreover, the extracts displayed satisfactory antioxidant activities, especially in inhibiting lipoperoxidation as assessed by the TBARS assay. Additionally, the extracts demonstrated effective inhibition against different strains of bacteria and fungi known as food contaminants. Taken together, these findings indicate that those extracts have the potential to be tested as natural antioxidants and preservatives with sustainable origins in food and beverage systems. Among the extraction methods evaluated, traditional maceration and UAE provided extracts with the highest antioxidant and antimicrobial activities. CONCLUSIONS: Our results suggest the opportunity to explore grape marc and seeds discarded by the winery industry in Portugal as natural sources of bioactive compounds, which could be employed as functional food ingredients or technological additives. The valorization of grape biowastes offers a promising strategy to reduce waste and harness their potential health benefits.


Assuntos
Eliminação de Resíduos , Vitis , Polifenóis/química , Vitis/química , Antioxidantes/química , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas em Tandem , Extratos Vegetais/química , Sementes/química
6.
Eur J Orthop Surg Traumatol ; 33(7): 2895-2902, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36897409

RESUMO

AIMS: The purpose of this study was to compare the impact of postoperative closed-incision negative-pressure wound therapy (ciNPWT) and conventional dressings in wound-related complications after bone tumor resection and reconstruction. PATIENTS AND METHODS: A total of 50 patients with bone tumors and clinical indication for wide resection and reconstruction were included and divided into two groups (A and B). Bone defect reconstructions were achieved with modular endoprosthesis or biologic techniques, mainly involving allografts with free vascularized fibula. Group A received ciNPWT, and Group B conventional dressings. Wound-related complications, including wound dehiscence, persistent wound leakage, surgical site infections (SSIs), and causes for surgical revision, were assessed. RESULTS: Nineteen patients were included in Group A and 31 in Group B. No significant differences were found between groups regarding epidemiologic and clinical presentation features, contrarily to reconstructive options, which were significantly different between both (Fisher = 10,100; p = 0.005). Additionally, Group A presented lower wound dehiscence rate (0 vs. 19.4%; χ2(1) = 4.179; p = 0.041), SSI rate (0 vs. 19.4%; χ2(1) = 4.179; p = 0.041), and surgical revision rate (5.3% vs. 32.3%; χ2(1) = 5.003; p = 0.025) compared to Group B. CONCLUSIONS: This is the first study reporting the impact of ciNPWT after bone tumor resection and reconstruction, and its results support a potential role for this technique in diminishing postoperative wound complications and SSIs. A multicentric randomized controlled trial may help clarify the role and impact of ciNPWT after bone tumor resection and reconstruction.


Assuntos
Neoplasias Ósseas , Tratamento de Ferimentos com Pressão Negativa , Ferida Cirúrgica , Humanos , Tratamento de Ferimentos com Pressão Negativa/métodos , Cicatrização , Ferida Cirúrgica/terapia , Infecção da Ferida Cirúrgica/etiologia , Infecção da Ferida Cirúrgica/prevenção & controle , Infecção da Ferida Cirúrgica/cirurgia , Extremidade Inferior , Neoplasias Ósseas/cirurgia
7.
Int J Mol Sci ; 23(22)2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-36430703

RESUMO

Sarcomas are rare malignant mesenchymal neoplasms, and the knowledge of tumor biology and genomics is scarce. Chemotherapy is the standard of care in advanced disease, with poor outcomes. Identifying actionable genomic alterations may offer effective salvage therapeutic options when previous lines have failed. Here, we report a retrospective cohort study of sarcoma patients followed at our center and submitted to comprehensive genomic profiling between January 2020 and June 2021. Thirty patients were included, most (96.7%) with reportable genomic alterations. The most common alterations were linked to cell cycle regulation (TP53, CDKN2A/B, and RB1 deletions and CDK4, MDM2, and MYC amplifications). Most patients (96.7%) had microsatellite stability and low tumor mutational burden (≤10 muts/megabase (Mb); median 2 Muts/Mb). Two-thirds of patients had actionable mutations for targeted treatments, including five cases with alterations amenable to targeted therapies with clinical benefit within the patient's tumor type, ten cases with targetable alterations with clinical benefit in other tumor types, and five cases with alterations amenable to targeting with drugs under investigation in a clinical trial setting. A significant proportion of cases in this study had actionable genomic alterations with available targeted drugs. Next-generation sequencing is a feasible option for identifying molecular drivers that can provide therapeutic options for individual patients. Molecular Tumor Boards should be implemented in the clinical practice to discuss genomic findings and inform clinically relevant targeted therapies.


Assuntos
Sarcoma , Neoplasias de Tecidos Moles , Humanos , Estudos Retrospectivos , Sarcoma/tratamento farmacológico , Sarcoma/genética , Perfil Genético , Genômica
8.
Int J Mol Sci ; 23(19)2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-36232732

RESUMO

Soft tissue sarcomas (STS) prognosis is disappointing, with current treatment strategies being based on a "fit for all" principle and not taking distinct sarcoma subtypes specificities and genetic/metabolic differences into consideration. The paucity of precision therapies in STS reflects the shortage of studies that seek to decipher the sarcomagenesis mechanisms. There is an urge to improve STS diagnosis precision, refine STS classification criteria, and increase the capability of identifying STS prognostic biomarkers. Single-omics and multi-omics studies may play a key role on decodifying sarcomagenesis. Metabolomics provides a singular insight, either as a single-omics approach or as part of a multi-omics strategy, into the metabolic adaptations that support sarcomagenesis. Although STS metabolome is scarcely characterized, untargeted and targeted metabolomics approaches employing different data acquisition methods such as mass spectrometry (MS), MS imaging, and nuclear magnetic resonance (NMR) spectroscopy provided important information, warranting further studies. New chromatographic, MS, NMR-based, and flow cytometry-based methods will offer opportunities to therapeutically target metabolic pathways and to monitorize the response to such metabolic targeting therapies. Here we provide a comprehensive review of STS omics applications, comprising a detailed analysis of studies focused on the metabolic landscape of these tumors.


Assuntos
Sarcoma , Neoplasias de Tecidos Moles , Biomarcadores , Humanos , Metaboloma , Metabolômica/métodos , Sarcoma/diagnóstico
9.
Molecules ; 27(2)2022 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-35056866

RESUMO

The use of natural colorants is needed to overcome consumer concerns regarding synthetic food colorants' safety. However, natural pigments have, in general, poor stability against environmental stresses such as temperature, ionic strength, moisture, light, and pH, among others. In this work, water-in-oil-in-water (W1/O/W2) emulsions were used as protective carriers to improve color stability of a hydrophilic Sambucus nigra L. extract against pH changes. The chemical system comprised water and corn oil as the aqueous and oil phases, respectively, and polyglycerol polyricinoleate (PGPR), Tween 80, and gum Arabic as stabilizers. The primary emulsion was prepared using a W1/O ratio of 40/60 (v/v). For the secondary emulsion, W1/O/W2, different (W1/O)/W2 ratios were tested with the 50/50 (v/v) formulation presenting the best stability, being selected as the coloring system to test in food matrices of different pH: natural yogurt (pH 4.65), rice drink (pH 6.01), cow milk (pH 6.47), and soy drink (pH 7.92). Compared to the direct use of the extract, the double emulsion solution gave rise to higher color stability with pH change and storage time, as corroborated by visual and statistical analysis.


Assuntos
Corantes/química , Emulsões/química , Sambucus nigra/química , Gorduras/química , Ácidos Graxos/química , Armazenamento de Alimentos , Interações Hidrofóbicas e Hidrofílicas , Extratos Vegetais/química , Temperatura , Fatores de Tempo , Água/química
10.
Dermatol Online J ; 28(1)2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35499414

RESUMO

A 76-year-old woman presented to the medical oncology outpatient clinic with painful, burning, pruritic erythematous plaques involving both palms and axillae that had suddenly appeared five days before. Examination revealed no additional relevant findings and laboratory studies did not show any alteration. The patient had been recently diagnosed with a high-grade angiosarcoma of the breast (probably radiation induced) and after frequent local recurrences, was being treated with liposomal doxorubicin (three cycles were administered, the last of which was seven days before the appearance of the mentioned lesions). Oral corticosteroids were started, treatment with liposomal doxorubicin was stopped, and cutaneous biopsies performed that revealed features compatible with toxic erythema of chemotherapy induced by liposomal doxorubicin. Complete resolution of the cutaneous lesions was verified one month after. No signs of recurrence of angiosarcoma were documented at follow-up three months later.


Assuntos
Antineoplásicos , Hemangiossarcoma , Idoso , Doxorrubicina/efeitos adversos , Doxorrubicina/análogos & derivados , Eritema/induzido quimicamente , Feminino , Humanos , Polietilenoglicóis
11.
Int J Mol Sci ; 22(2)2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33467481

RESUMO

Osteosarcoma (OS) is a rare condition with very poor prognosis in a metastatic setting. Basic research has enabled a better understanding of OS pathogenesis and the discovery of new potential therapeutic targets. Phase I and II clinical trials are already ongoing, with some promising results for these patients. This article reviews OS pathogenesis and new potential therapeutic targets.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Neoplasias Ósseas/tratamento farmacológico , Terapia de Alvo Molecular/métodos , Osteossarcoma/tratamento farmacológico , Receptor IGF Tipo 1/antagonistas & inibidores , Antineoplásicos Imunológicos/uso terapêutico , Neoplasias Ósseas/metabolismo , Humanos , Osteossarcoma/metabolismo , Prognóstico , Receptor ErbB-2/antagonistas & inibidores , Receptor ErbB-2/metabolismo , Receptor IGF Tipo 1/metabolismo , Trastuzumab/uso terapêutico
12.
Int J Mol Sci ; 22(6)2021 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-33803866

RESUMO

Understanding the effect of extreme temperatures and elevated air (CO2) is crucial for mitigating the impacts of the coffee industry. In this work, leaf transcriptomic changes were evaluated in the diploid C. canephora and its polyploid C. arabica, grown at 25 °C and at two supra-optimal temperatures (37 °C, 42 °C), under ambient (aCO2) or elevated air CO2 (eCO2). Both species expressed fewer genes as temperature rose, although a high number of differentially expressed genes (DEGs) were observed, especially at 42 °C. An enrichment analysis revealed that the two species reacted differently to the high temperatures but with an overall up-regulation of the photosynthetic machinery until 37 °C. Although eCO2 helped to release stress, 42 °C had a severe impact on both species. A total of 667 photosynthetic and biochemical related-DEGs were altered with high temperatures and eCO2, which may be used as key probe genes in future studies. This was mostly felt in C. arabica, where genes related to ribulose-bisphosphate carboxylase (RuBisCO) activity, chlorophyll a-b binding, and the reaction centres of photosystems I and II were down-regulated, especially under 42°C, regardless of CO2. Transcriptomic changes showed that both species were strongly affected by the highest temperature, although they can endure higher temperatures (37 °C) than previously assumed.


Assuntos
Dióxido de Carbono/farmacologia , Coffea/genética , Diploide , Regulação da Expressão Gênica de Plantas , Poliploidia , Temperatura , Transcriptoma/genética , Coffea/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Ontologia Genética , Genótipo , Fotossíntese/efeitos dos fármacos , Transcriptoma/efeitos dos fármacos
13.
Molecules ; 26(8)2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33923713

RESUMO

Microencapsulation procedures have recently focused attention on designing novel microspheres via green synthesis strategies. The use of chitosan (CS) as an encapsulating material has increased interest due to its unique bioactive properties and the various crosslinking possibilities offered by their functional groups. The consolidation of the microspheres by physical crosslinking using sodium tripolyphosphate (TPP) combined with chemical crosslinking using vanillin (VA) open new opportunities in the framework of green dual crosslinking strategies. The developed strategy, a straightforward technique based on an aqueous medium avoiding complex separation/washing steps, offers advantages over the processes based on VA, mostly using water-in-oil emulsion approaches. Thus, in this work, the combination of TPP crosslinking (3, 5, and 10 wt.%) via spray-coagulation technique with two VA crosslinking methods (in situ and post-treatment using 1 wt.% VA) were employed in the preparation of microspheres. The microspheres were characterized concerning morphology, particle size, physicochemical properties, thermal stability, and swelling behavior. Results revealed that the combination of 5 wt.% TPP with in situ VA crosslinking led to microspheres with promising properties, being an attractive alternative for natural bioactives encapsulation due to the green connotations associated with the process.


Assuntos
Benzaldeídos/química , Quitosana/química , Polifosfatos/química , Emulsões , Microesferas
14.
Am J Transplant ; 20(4): 1188-1191, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31654479

RESUMO

Kidney transplant (KT) recipients have an increased risk for urothelial carcinoma. A role for JC virus (JCV) in human cancers is not yet proved but there is an increasingly reported association between BK virus (BKV) nephropathy and renourinary neoplasms. We report a KT recipient who developed a high-grade urothelial carcinoma 5 years after a diagnosis of JCV nephropathy and 9 years after kidney transplantation. Neoplastic tissue was positive for JCV DNA by real-time polymerase chain reaction (PCR). Immunochemical staining showed strong positivity for cell cycle markers (p16, p53, and Ki67) and for early viral protein JCV large T antigen (JCV LTag; using a broad polyomavirus antibody); however, late viral protein (VP1) stained negative. In contrast, in non-neoplastic urothelium, JCV DNA and all immunochemical markers were negative. These facts suggest that malignancy was induced by JCV. To the best of our knowledge, this is the first report of urothelial high-grade carcinoma associated with JCV nephropathy in a KT recipient.


Assuntos
Vírus BK , Carcinoma de Células de Transição , Vírus JC , Transplante de Rim , Infecções por Polyomavirus , Infecções Tumorais por Vírus , Neoplasias da Bexiga Urinária , Vírus BK/genética , DNA Viral/genética , Humanos , Vírus JC/genética , Transplante de Rim/efeitos adversos , Infecções por Polyomavirus/complicações , Retroviridae , Neoplasias da Bexiga Urinária/etiologia
15.
Anal Bioanal Chem ; 412(24): 6381-6389, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32270246

RESUMO

Lercanidipine, a third-generation dihydropyridine calcium L-type channel blocker, redox behavior at different carbon electrode materials, in a wide pH range, using cyclic, square-wave, and differential pulse voltammetry, was studied. A comparison was made between unmodified glassy carbon electrode (GCE) and boron-doped diamond electrode (BDDE), and GCE and BDDE modified with a carbon black (CB) nanoparticle embedded within a dihexadecylphosphate (DHP) nanostructured film (CB-DHP/GCE and CB-DHP/BDDE). Lercanidipine oxidation, for 3.4 < pH < 9.5, is an irreversible, diffusion-controlled, pH-dependent process that occurs in two consecutive steps, with the transfer of one electron and one proton, at the N1 and C4 positions in the 1,4-dihydropyridine ring. For pH > 9.5, both oxidation processes are pH-independent and a pKa = 9.40 was determined. Lercanidipine reduction at pH = 7.0 is an irreversible process, and the lercanidipine reduction products are electroactive and follow a reversible electron transfer reaction. Lercanidipine electroanalytical determination, at a nanostructured GCE modified with a CB-DHP film (CB-DHP/GCE), with no need for N2 purging, with a detection limit of 0.058 µM (3.58 × 10-5 g L-1) and a quantification limit of 0.176 µM (1.08 × 10-4 g L-1), was achieved. Graphical abstract.


Assuntos
Bloqueadores dos Canais de Cálcio/química , Di-Hidropiridinas/química , Boro/química , Técnicas Eletroquímicas , Eletrodos , Elétrons , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Oxirredução , Prótons , Fuligem/química
16.
Mikrochim Acta ; 187(11): 609, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-33057990

RESUMO

Electropolymerization of thionine (TH) on multiwalled carbon nanotube (MWCNT)-modified glassy carbon electrodes (GCE) in ethaline deep eutectic solvent (DES) was carried out for the first time, to prepare poly(thionine) (PTH) films with different nanostructured morphologies. PTH films were formed on MWCNT/GCE by potential cycling electropolymerization in ethaline with the addition of different acid dopants CH3COOH, HClO4, HNO3, H2SO4 and HCl, acetic acid being the best. The electropolymerization process was monitored with an electrochemical quartz crystal microbalance. The polymerization scan rate was a key factor affecting the electrochemical and morphological properties of the PTHEthaline-CH3COOH/MWCNT/GCE; electrodeposition at 200 mV s-1 showing the best performance. The PTH/MWCNT/GCE platform was characterized using cyclic and differential pulse voltammetry, electrochemical impedance spectroscopy and scanning electron microscopy. The analytical characteristics of the PTH films were evaluated for sensing of ascorbic acid and biosensing of uric acid. The developed sensor exhibited a low detection limit (1.1 µM), wide linear range (2.8-3010 µM) and high sensitivity (1134 µA cm-2 mM-1) for ascorbic acid. After immobilization of uricase, UOx, on PTH/MWCNT/GCE, the biosensor was successfully applied to the determination of uric acid, with fast response (˂ 7 s), good sensitivity (450 µA cm-2 mM-1, wide linear range (0.48-279 µM) and low detection limit (58.9 nM), better than in the literature and than with PTH prepared in aqueous solution. The determination of uric acid in synthetic urine samples was successfully tested and the mean analytical recovery was 100.8 ± 1.4%. This is a promising approach for the determination of uric acid in real samples. Graphical abstract.


Assuntos
Solventes Eutéticos Profundos/química , Técnicas Eletroquímicas/métodos , Nanotubos de Carbono/química , Polímeros/química , Ácido Acético , Ácido Ascórbico/análise , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Colina/química , Técnicas Eletroquímicas/instrumentação , Eletrodos , Enzimas Imobilizadas/química , Etilenoglicol/química , Limite de Detecção , Fenotiazinas/química , Polimerização , Urato Oxidase/química , Ácido Úrico/química , Ácido Úrico/urina
17.
Int J Mol Sci ; 21(23)2020 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-33287164

RESUMO

As atmospheric [CO2] continues to rise to unprecedented levels, understanding its impact on plants is imperative to improve crop performance and sustainability under future climate conditions. In this context, transcriptional changes promoted by elevated CO2 (eCO2) were studied in genotypes from the two major traded coffee species: the allopolyploid Coffea arabica (Icatu) and its diploid parent, C. canephora (CL153). While Icatu expressed more genes than CL153, a higher number of differentially expressed genes were found in CL153 as a response to eCO2. Although many genes were found to be commonly expressed by the two genotypes under eCO2, unique genes and pathways differed between them, with CL153 showing more enriched GO terms and metabolic pathways than Icatu. Divergent functional categories and significantly enriched pathways were found in these genotypes, which altogether supports contrasting responses to eCO2. A considerable number of genes linked to coffee physiological and biochemical responses were found to be affected by eCO2 with the significant upregulation of photosynthetic, antioxidant, and lipidic genes. This supports the absence of photosynthesis down-regulation and, therefore, the maintenance of increased photosynthetic potential promoted by eCO2 in these coffee genotypes.


Assuntos
Dióxido de Carbono/metabolismo , Coffea/genética , Coffea/metabolismo , Regulação da Expressão Gênica de Plantas , Transcriptoma , Pressão do Ar , Biologia Computacional/métodos , Perfilação da Expressão Gênica , Ontologia Genética , Genótipo , Anotação de Sequência Molecular
18.
Molecules ; 25(9)2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-32365923

RESUMO

Water-in-oil (W/O) emulsions have high potential for several industrial areas as delivery systems of hydrophilic compounds. In general, they are less studied than oil-in-water (O/W) systems, namely in what concerns the so-called fluid systems, partly due to problems of instability. In this context, this work aimed to produce stable W/O emulsions from a natural oil, sweet almond oil, to be further tested as vehicles of natural hydrophilic extracts, here exemplified with an aqueous cinnamon extract. Firstly, a base W/O emulsion using a high-water content (40/60, v/v) was developed by testing different mixtures of emulsifiers, namely Tween 80 combined with Span 80 or Span 85 at different contents. Among the tested systems, the one using a 54/46 (v/v) Span 80/Tween 80 mixture, and subjected to 12 high-pressure homogenizer (HPH) cycles, revealed to be stable up to 6 months, being chosen for the subsequent functionalization tests with cinnamon extract (1.25-5%; w/v; water-basis). The presence of cinnamon extract leaded to changes in the microstructure as well as in the stability. The antimicrobial and antioxidant analysis were evidenced, and a sustained behavior compatible with an extract distribution within the two phases, oil and water, in particular for the higher extract concentration, was observed.


Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Portadores de Fármacos/química , Emulsões/química , Óleos/química , Água/química , Antioxidantes/química , Antioxidantes/farmacologia , Cinnamomum zeylanicum/química , Interações Hidrofóbicas e Hidrofílicas , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , Extratos Vegetais/farmacologia
19.
Naturwissenschaften ; 105(11-12): 63, 2018 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-30311012

RESUMO

New finds of bones of the Egyptian Mongoose (Herpestes ichneumon), one from Portugal and one from Spain, were directly 14C dated to the first century AD. While the Portuguese specimen was found without connection to the Chalcolithic occupation of the Pedra Furada cave where it was recovered, the Spanish find, collected in the city of Mérida, comes from a ritual pit that also contained three human and 40 dog burials. The finds reported here show that the Egyptian mongoose, contrary to the traditional and predominant view, did not first arrive in the Iberian Peninsula during the Muslim occupation of Iberia. Instead, our findings are consistent with the hypothesis that the species was first introduced by the Romans, or at least sometime during the Roman occupation of Hispania. Therefore, radiocarbon dating of new archaeological finds of bones of the Egyptian Mongoose (Herpestes ichneumon) in the Iberian Peninsula push back the confirmed presence of the species in the region by approximately eight centuries, as the previously oldest dated record is from the ninth century. With these new dates, there are now a total of four 14C dated specimens of Egyptian mongooses from the Iberian Peninsula, and all of these dates fall within the last 2000 years. This offers support for the hypothesis that the presence of the species in Iberia is due to historical introductions and is at odds with a scenario of natural sweepstake dispersal across the Straits of Gibraltar in the Late Pleistocene (126,000-11,700 years ago), recently proposed based on genetic data.


Assuntos
Herpestidae , Animais , Osso e Ossos/química , Radioisótopos de Carbono/análise , Egito , História Antiga , Portugal , Espanha
20.
Adv Exp Med Biol ; 1096: 117-133, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30324351

RESUMO

Prostate cancer is the most common malignancy in men, and remains the second leading cause of cancer-related death in this gender [1]. Data suggests that 10-20% of patients with prostate cancer metastasis develop castration-resistant prostate cancer (CRPC) within 5 years of follow-up, and that the median survival since development of castration resistance is approximately 14 months (range 9-30) [2]. Additionally, patients with non-metastatic CRPC are at higher risk of disease progression. Approximately 15-33% of patients develop metastasis within 2 years, increasing the mortality burden in this population [3, 4].


Assuntos
Neoplasias de Próstata Resistentes à Castração/diagnóstico , Neoplasias de Próstata Resistentes à Castração/terapia , Progressão da Doença , Humanos , Masculino
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