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1.
Mikrochim Acta ; 191(10): 633, 2024 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-39342530

RESUMO

The development of a tailored filament is reported composed of reduced graphene oxide (rGO) and carbon black (CB) in a polylactic acid (PLA) matrix and its use in the production of electrochemical sensors. The electrodes containing rGO showed superior performance when compared with  those prepared in the absence of this material. Physicochemical and electrochemical characterizations of the electrodes showed the successful incorporation of both rGO and CB and an improved conductivity in the presence of rGO (lower resistance to charge transfer). As a proof-of-concept, the developed electrodes were applied to the detection of the forensic analytes TNT and cocaine. The electrodes containing rGO presented a superior analytical performance for both TNT and cocaine detection, showing the lower limit of detection values (0.22 and 2.1 µmol L-1, respectively) in comparison with pure CB-PLA electrodes (0.93 and 11.3 µmol L-1, respectively). Besides, better-defined redox peaks were observed, especially for TNT, as well as increased sensitivity for both molecules.

2.
Anal Chem ; 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39236255

RESUMO

Three-dimensional (3D) printing is an emerging technology to develop devices on a large scale with potential application for electroanalysis. However, 3D-printed electrodes, in their native form, provide poor electrochemical response due to the presence of a high percentage of thermoplastic polymer in the conductive filaments. Therefore, surface treatments are usually required to remove the nonconductive material from the 3D-printed electrode surfaces, providing a dramatic improvement in the electroanalytical performance. However, these procedures are time-consuming, require bulky equipment, or even involve non-eco-friendly protocols. Herein, we demonstrated that portable and low-cost atmospheric air plasma jet pens can be used to activate electrodes additively manufactured using a commercial poly(lactic acid) filament containing carbon black as conductive filler, improving the electrochemical activity. Remarkable electrochemical results were obtained (voltammetric profile) using [Fe(CN)6]3-/4-, dopamine and [Ru(NH3)6]2+/3+ as redox probes. Microscopic, spectroscopic, and electrochemical techniques revealed that the air-plasma jet pen removes the excess PLA on the 3D-printed electrode surface, exposing the conductive carbon black particles and increasing the surface area. The performance of the treated electrode was evaluated by the quantification of capsaicin in pepper sauce samples, with a limit of detection of 3 nM, suitable for analysis of food samples. Recovery values from 94% to 101% were obtained for the analysis of spiked samples. The new treatment generated by a plasma jet pen is an alternative approach to improve the electrochemical activity of 3D-printed electrodes that present sluggish kinetics with great advantages over previous protocols, including low-cost, short time of treatment (2 min), environmentally friendly protocol (reagentless), and portability (hand-held pen).

3.
Microb Biotechnol ; 17(6): e14503, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38829373

RESUMO

Rare earth elements (REEs) are critical for our modern lifestyles and the transition to a low-carbon economy. Recent advances in our understanding of the role of REEs in biology, particularly methylotrophy, have provided opportunities to explore biotechnological innovations to improve REE mining and recycling. In addition to bacterial accumulation and concentration of REEs, biological REE binders, including proteins (lanmodulin, lanpepsy) and small molecules (metallophores and cofactors) have been identified that enable REE concentration and separation. REE-binding proteins have also been used in several mechanistically distinct REE biosensors, which have potential application in mining and medicine. Notably, the role of REEs in biology has only been known for a decade, suggesting their considerable scope for developing new understanding and novel applications.


Assuntos
Bactérias , Metais Terras Raras , Metais Terras Raras/metabolismo , Metais Terras Raras/química , Bactérias/metabolismo , Bactérias/genética , Bactérias/química , Biotecnologia/métodos
4.
Plant Dis ; 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38803068

RESUMO

In October 2023, a Connecticut grower contacted The Connecticut Agricultural Experiment Station about a field of strawberry plants (Fragaria × ananassa) (cv. Ruby June) showing symptoms of severe leaf spotting and visual wilting. Upon visiting the field, leaves had lesions with a diffuse black halo and a light brown center and wilting symptoms, which appeared driven by petiole lesions and presented as dark brown stripes with a reddish-purple halo. Symptoms were observed on 80 to 90% of plants within the block, nearly all of which (>90%) presented with both leaf spots and severe wilting. Diseased tissue was collected from 20 leaves and 25 petioles, sterilized in 0.6% NaOCL, and plated on potato dextrose agar. After hyphal tipping a morphologically identical fungus was isolated from 70% of leaves and 88% of petioles, which formed a dense white mycelial mat with moderate aerial mycelium and conidiomata that exuded dark brown conidial masses. The underside of the mycelial mat was yellowish. Conidia were fusoid, ellipsoid, straight to slightly curved, 4-septate with a single basal appendage and 2-5 apical, matching the description of species within the genus Neopestalotiopsis (Maharachchikumbura et al. 2014). The average conidia (n=74) length, not including appendages, was 29.9 ± 2.1 µm and the average width, at the widest point, was 7.5 ± 0.7 µm. Aerial hyphae were collected from two isolates, CT58-1 and CT62-2, and DNA was extracted for further molecular characterization. PCR was performed with primers targeting actin (ACT), ß-tubulin (TUB2), and ITS prior to amplicon sequencing (Carbone and Kohn 1999; Hassan et al. 2018). Sequences were queried against the NCBI whole genome shotgun database, and aligned sequences from 13 species (including Neopestalotiopsis, Pestalotiopsis, and Pseudopestalotiopsis) were collected for each locus. Sequences were aligned, trimmed, and concatenated using Mega11, and IQ-TREE was employed for model selection (Nguyen et al. 2015; Tamura et al. 2021). A maximum-likelihood tree placed the isolates in a high-confidence cluster with Neopestalotiopsis rosae, confirming this placement of these isolates within the genus (CT58-1 Accession #: PP715979-89; PP707735). To confirm pathogenicity, CT58-1 was grown on autoclaved strawberry leaves to induce sporulation, and a suspension of 105 spores/ml was made. Five milliliters of this spore suspension was sprayed on six 6-week-old strawberries (cv. Jewel), and water was sprayed on the same number of control plants. Plants were at 100% humidity for two days and then kept in the greenhouse for 3 weeks to observe symptoms. Inoculated plants presented with identical leaf spot and petiole lesions to field samples and no visual symptoms were observed on control plants. New isolations were made from infected petioles, which produced morphologically identical spores to those described above, and ITS/ACT loci sequencing yielded sequences identical to those of CT58-1. Spore production and plant inoculations were repeated with this new isolate, and identical symptoms were observed. This is the first report of Neopestalotiopsis infecting strawberries in New England and given the high disease incidence in the initial infected field and relative lack of disease in a neighboring field, it is likely that this pathogen was introduced on bare root plants. As the plants were sourced from a nursery in Ontario, Canada, it is likely that the pathogen is capable of overwintering in the Northeastern United States.

5.
Int J Biol Macromol ; 263(Pt 1): 130306, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38387641

RESUMO

Peroxidases (EC 1.11.1.7) are involved in a wide range of physiological processes, hence their broad distribution across biological systems. These proteins can be classified as haem or non-haem enzymes. According to the RedOxiBase database, haem peroxidases are approximately 84 % of all known peroxidase enzymes. Class III plant peroxidases are haem-enzymes that share similar three-dimensional structures and a common catalytic mechanism for hydrogen peroxide degradation. They exist as large multigene families and are involved in metabolizing Reactive Oxygen Species (ROS), hormone synthesis and decomposition, fruit growth, defense, and cell wall synthesis and maintenance. As a result, plant peroxidases gained attention in research and became one of the most extensively studied groups of enzymes. This review provides an update on the database, classification, phylogeny, mechanism of action, structure, and physiological functions of class III plant peroxidases.


Assuntos
Peroxidase , Peroxidases , Peroxidases/metabolismo , Plantas , Espécies Reativas de Oxigênio/metabolismo , Heme
6.
PLoS One ; 18(12): e0295832, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38150452

RESUMO

AIMS: Evaluate the impact of an intervention program in non-adherent patients with ulcerative colitis. METHODS: Parallel controlled randomized clinical trial (1:1), approved by the ethics committee (No. 3.068.511/2018) and registered at The Brazilian Clinical Trials Registry (No. RBR-79dn4k). Non-adherent ulcerative colitis patients according to the Morisky-Green-Levine-test were included. Recruitment began in August 2019 until August 2020, with 6-month follow-up. All participants received standard usual care, and additionally the intervention group received educational (video, educational leaflet, verbal guidance) and behavioral interventions (therapeutic scheme, motivational and reminder type short message services). Researchers were blinded for allocation prior to data collection at Visits 1 and 2 (0 and 6 months). Primary outcome: 180-day adherence rate, with relative risk 95%CI. Secondary outcome: 180-day quality of life according to SF-36 domains, using Student's t test. Variables with p<0.20 were selected for regression. Analysis included data from August/2019 to May/2021. RESULTS: Forty-six and 49 participants were allocated in control and intervention groups, respectively. Two were excluded due to intervention refusal, and 4 and 6 were lost to follow-up in control and intervention groups. There was no post-intervention adherence rate difference, even after adjustment for type of non-adherence (unintentional/both/intentional) as confounder, or if considered as adherent the intervention group participants lost in follow-up. Interventions promoted better quality of life scores even after multivariate analysis for "Pain", when adjusted for ulcerative colitis severity, sex, and marital status (ß = 18.352, p = 0.004), "Vitality", when adjusted for ulcerative colitis severity (ß = 10.568, p = 0.015) and "Emotional Aspects", when adjusted for disease severity, income, and education (ß = 24.907, p = 0.041). CONCLUSIONS: The intervention program was not able to produce a significant medication adherence rate difference between comparative groups, however, there was a significant improvement in quality of life. Study limitations may include: sample size calculated to identify differences of 30%, leading to a possible insufficient power; non blinded participants, exposing the results to the risk of performance bias; outcomes based on self-reported data.


Assuntos
Colite Ulcerativa , Envio de Mensagens de Texto , Humanos , Colite Ulcerativa/tratamento farmacológico , Qualidade de Vida , Adesão à Medicação , Terapia Comportamental
7.
Nutr Rev ; 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38114090

RESUMO

CONTEXT: There is growing evidence that insufficient dietary intake is associated with sarcopenia. OBJECTIVE: In this systematic review and meta-analysis, the energy and nutrient intakes by people with and without sarcopenia were compared using only the European Working Group on Sarcopenia in Older People 2010 (EWGSOP1) and 2019 (EWGSOP2) consensus diagnostic criteria. DATA SOURCES: Only observational studies that compared energy and nutrient intake from food alone by individuals with and without sarcopenia were included. Studies were searched in the following databases: Embase, PubMed, Scopus, Web of Science, Lilacs, Ovid, and Scopus. The review followed the PRISMA checklist and submitted the protocol to PROSPERO. DATA EXTRACTION: Data were extracted by 2 authors independently. The methodological quality of the studies was assessed using the Newcastle-Ottawa scale. DATA ANALYSIS: A total of 8648 articles were identified and 12 were selected. Among individuals with sarcopenia, lower intakes of energy and some nutrients, mainly with antioxidant properties, were observed compared with those without sarcopenia. Meta-analyses showed that individuals with sarcopenia consume fewer calories/day than individuals without sarcopenia (n = 10 studies; standardized mean difference (SMD) -0.15; 95% confidence interval: -0.29, -0.01) diagnosed by EWGSOP1 and EWGSOP2. Individuals with sarcopenia consume less omega-3, folate, magnesium, phosphorus, selenium, zinc, and vitamins C, D, and E when compared with those without sarcopenia. CONCLUSION: The results of the present study suggest that insufficient intake of energy and nutrients with antioxidant potential may be associated with sarcopenia. SYSTEMATIC REVIEW REGISTRATION: PROSPERO registration no. CRD 42020195698.

8.
Nat Med ; 29(10): 2509-2517, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37696933

RESUMO

Pathogen genome sequencing during epidemics enhances our ability to identify and understand suspected clusters and investigate their relationships. Here, we combine genomic and epidemiological data of the 2022 mpox outbreak to better understand early viral spread, diversification and transmission dynamics. By sequencing 52% of the confirmed cases in Portugal, we identified the mpox virus sublineages with the highest impact on case numbers and fitted them into a global context, finding evidence that several international sublineages probably emerged or spread early in Portugal. We estimated a 62% infection reporting rate and that 1.3% of the population of men who have sex with men in Portugal were infected. We infer the critical role played by sexual networks and superspreader gatherings, such as sauna attendance, in the dissemination of mpox virus. Overall, our findings highlight genomic epidemiology as a tool for the real-time monitoring and control of mpox epidemics, and can guide future vaccine policy in a highly susceptible population.


Assuntos
Mpox , Minorias Sexuais e de Gênero , Masculino , Humanos , Portugal/epidemiologia , Homossexualidade Masculina , Surtos de Doenças , Análise por Conglomerados
9.
Nat Commun ; 14(1): 4146, 2023 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-37438395

RESUMO

The blast fungus Magnaporthe oryzae produces invasive hyphae in living rice cells during early infection, separated from the host cytoplasm by plant-derived interfacial membranes. However, the mechanisms underpinning this intracellular biotrophic growth phase are poorly understood. Here, we show that the M. oryzae serine/threonine protein kinase Rim15 promotes biotrophic growth by coordinating cycles of autophagy and glutaminolysis in invasive hyphae. Alongside inducing autophagy, Rim15 phosphorylates NAD-dependent glutamate dehydrogenase, resulting in increased levels of α-ketoglutarate that reactivate target-of-rapamycin (TOR) kinase signaling, which inhibits autophagy. Deleting RIM15 attenuates invasive hyphal growth and triggers plant immunity; exogenous addition of α-ketoglutarate prevents these effects, while glucose addition only suppresses host defenses. Our results indicate that Rim15-dependent cycles of autophagic flux liberate α-ketoglutarate - via glutaminolysis - to reactivate TOR signaling and fuel biotrophic growth while conserving glucose for antioxidation-mediated host innate immunity suppression.


Assuntos
Ascomicetos , Oryza , Hifas , Ácidos Cetoglutáricos , Autofagia , Proteínas Serina-Treonina Quinases , Glucose
10.
Enzyme Microb Technol ; 169: 110268, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37300919

RESUMO

Enzyme immobilization offers considerable advantage for biocatalysis in batch and continuous flow reactions. However, many currently available immobilization methods require that the surface of the carrier is chemically modified to allow site specific interactions with their cognate enzymes, which requires specific processing steps and incurs associated costs. Two carriers (cellulose and silica) were investigated here, initially using fluorescent proteins as models to study binding, followed by assessment of industrially relevant enzyme performance (transaminases and an imine reductase/glucose oxidoreductase fusion). Two previously described binding tags, the 17 amino acid long silica-binding peptide from the Bacillus cereus CotB protein and the cellulose binding domain from the Clostridium thermocellum, were fused to a range of proteins without impairing their heterologous expression. When fused to a fluorescent protein both tags conferred high avidity specific binding with their respective carriers (low nanomolar Kd values). The CotB peptide (CotB1p) induced protein aggregation in the transaminase and imine reductase/glucose oxidoreductase fusions when incubated with the silica carrier. The Clostridium thermocellum cellulose binding domain (CBDclos) allowed immobilization of all the proteins tested, but immobilization led to loss of enzymatic activity in the transaminases (< 2-fold) and imine reductase/glucose oxidoreductase fusion (> 80%). A transaminase-CBDclos fusion was then successfully used to demonstrate the application of the binding tag in repetitive batch and a continuous-flow reactor.


Assuntos
Celulose , Enzimas Imobilizadas , Biocatálise , Enzimas Imobilizadas/metabolismo , Celulose/metabolismo , Oxirredutases/metabolismo , Peptídeos/metabolismo , Transaminases/metabolismo , Dióxido de Silício/química , Glucose Desidrogenase/metabolismo
11.
Biosensors (Basel) ; 13(6)2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37367011

RESUMO

A rapid and simple method for the amperometric determination of glucose using a nanocomposite film of nickel oxyhydroxide and multi-walled carbon nanotube (MWCNTs) was evaluated. The NiHCF)/MWCNT electrode film was fabricated using the liquid-liquid interface method, and it was used as a precursor for the electrochemical synthesis of nickel oxy-hydroxy (Ni(OH)2/NiOOH/MWCNT). The interaction between nickel oxy-hydroxy and the MWCNTs provided a film that is stable over the electrode surface, with high surface area and excellent conductivity. The nanocomposite presented an excellent electrocatalytic activity for the oxidation of glucose in an alkaline medium. The sensitivity of the sensor was found to be 0.0561 µA µmol L-1, and a linear range from 0.1 to 150 µmol L-1 was obtained, with a good limit of detection (0.030 µmol L-1). The electrode exhibits a fast response (150 injections h-1) and a sensitive catalytic performance, which may be due to the high conductivity of MWCNT and the increased active surface area of the electrode. Additionally, a minimal difference in the slopes for ascending (0.0561 µA µmol L-1) and descending (0.0531 µA µmol L-1) was observed. Moreover, the sensor was applied to the detection of glucose in artificial plasma blood samples, achieving values of 89 to 98% of recovery.


Assuntos
Nanotubos de Carbono , Níquel , Glucose , Oxirredução , Eletrodos , Impressão Tridimensional , Técnicas Eletroquímicas/métodos
13.
Pathogens ; 12(4)2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-37111417

RESUMO

Grazing systems have great potential to promote animal welfare by allowing animals to express natural behaviours, but they also present risks to the animals. Diseases caused by gastrointestinal nematodes are some of the most important causes of poor ruminant health and welfare in grazing systems and cause important economic losses. Reduced growth, health, reproduction and fitness, and negative affective states that indicate suffering are some of the negative effects on welfare in animals infected by gastrointestinal nematode parasitism. Conventional forms of control are based on anthelmintics, but their growing inefficiency due to resistance to many drugs, their potential for contamination of soil and products, and negative public opinion indicate an urgency to seek alternatives. We can learn to deal with these challenges by observing biological aspects of the parasite and the host's behaviour to develop managements that have a multidimensional view that vary in time and space. Improving animal welfare in the context of the parasitic challenge in grazing systems should be seen as a priority to ensure the sustainability of livestock production. Among the measures to control gastrointestinal nematodes and increase animal welfare in grazing systems are the management and decontamination of pastures, offering multispecies pastures, and grazing strategies such as co-grazing with other species that have different grazing behaviours, rotational grazing with short grazing periods, and improved nutrition. Genetic selection to improve herd or flock parasite resistance to gastrointestinal nematode infection may also be incorporated into a holistic control plan, aiming at a substantial reduction in the use of anthelmintics and endectocides to make grazing systems more sustainable.

14.
BMC Gastroenterol ; 23(1): 94, 2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-36977983

RESUMO

BACKGROUND: Evidence indicates that inflammation in Inflammatory Bowel Disease (IBD) is associated with increased systemic levels of reactive oxygen species. Systemic oxidative stress has been associated with reduced levels of plasma thiols. Less invasive tests capable of reflecting and predicting IBD activity are increasingly sought after. We sought to systematically review the evidence inherent in serum thiol levels as a marker of Crohn's Disease and Ulcerative Colitis activity (PROSPERO: CRD42021255521). METHODS: The highest quality documents for systematic reviews standards were used as reference. Articles were searched on Medline via PubMed, VHL, LILACS, WOS, EMBASE, SCOPUS, COCHRANE, CINAHL, OVID, CTGOV, WHO/ICTRP, OPENGREY, BDTD and CAPES, between August, 03 and September, 03 on 2021. Descriptors were defined according to the Medical Subject Heading. Of the 11 articles selected for full reading, 8 were included in the review. It was not possible to perform a pooled analysis of the studies, as there were no combinable studies between subjects with active IBD and controls/inactive disease. RESULTS: Findings from the individual studies included in this review suggest an association between disease activity and systemic oxidation, as measured by serum thiol levels, however, there are limitations that preclude weighting the study results in a meta-analysis. CONCLUSIONS: We recommend conducting better-designed and controlled studies, that include individuals of both phenotypes and at different stages of IBD, involving a larger number of participants, using the standardization of the technique for measuring serum thiols, to confirm whether thiols can be a good parameter for monitoring the clinical course of these intestinal diseases and the degree of clinical applicability.


Assuntos
Colite Ulcerativa , Doença de Crohn , Doenças Inflamatórias Intestinais , Humanos , Colite Ulcerativa/complicações , Doença de Crohn/complicações , Doenças Inflamatórias Intestinais/diagnóstico , Doenças Inflamatórias Intestinais/complicações , Compostos de Sulfidrila
16.
Cureus ; 15(1): e33312, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36741648

RESUMO

Fungal endocarditis is a rare and fatal condition, with a mortality of up to 75%, affecting immunocompromised hosts with a predisposing condition, namely, a history of previous cardiac or noncardiac surgery. Embolization is frequent, accounting for 44% of cases, and as the most common site is the brain, it can cause leptomeningitis, parenchymal granulomas, or abscesses. This case report describes a man with aortic valve replacement one year ago and a recent carotid endarterectomy who was admitted with fever and neurological deficits. The workup permitted a diagnosis of fungal endocarditis, and the patient underwent a combined and aggressive treatment approach with antifungal therapy and surgery, with a successful replacement of the aortic valve. During hospitalization, the patient's neurological status deteriorated, and a cerebral abscess was discovered on the left frontal lobe. Despite the poor prognosis, the patient recovered slowly and was discharged from the hospital three months later. The present case highlights the high index of suspicion needed for the diagnosis and the need for a multidisciplinary team to approach these patients to achieve a positive outcome.

17.
Mol Plant Microbe Interact ; 36(6): 372-380, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36847650

RESUMO

Root-knot nematodes (RKN) (Meloidogyne spp.) represent one of the most damaging groups of plant-parasitic nematodes. They secrete effector proteins through a protrusible stylet to manipulate host cells for their benefit. Stylet-secreted effector proteins are produced within specialized secretory esophageal gland cells, one dorsal gland (DG) and two subventral glands (SvG), whose activity differ throughout the nematode life cycle. Previous gland transcriptomic profiling studies identified dozens of candidate RKN effectors but were focused on the juvenile stages of the nematode, when the SvGs are most active. We developed a new approach to enrich for the active DGs of M. incognita adult female RKN for RNA and protein extraction. Female heads were manually cut from the body, and a combination of sonication and vortexing was used to dislodge contents inside the heads. DG-enriched fractions were collected by filtering, using cell strainers. Comparative transcriptome profiling of pre-parasitic second-stage juveniles, female heads, and DG-enriched samples was conducted using RNA sequencing. Application of an established effector mining pipeline led to the identification of 83 candidate effector genes upregulated in DG-enriched samples of adult females that code for proteins with a predicted signal peptide but lack transmembrane domains or homology to proteins in the free-living nematode Caenorhabditis elegans. In situ hybridization resulted in the identification of 14 new DG-specific candidate effectors expressed in adult females. Taken together, we have identified novel candidate Meloidogyne effector genes that may have essential roles during later stages of parasitism. [Formula: see text] Copyright © 2023 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.


Assuntos
Nematoides , Parasitos , Tylenchoidea , Animais , Feminino , Proteínas de Helminto/genética , Proteínas de Helminto/metabolismo , Plantas/genética , Perfilação da Expressão Gênica , Parasitos/genética , Caenorhabditis elegans/genética , Tylenchoidea/genética , Doenças das Plantas/parasitologia
18.
J Agric Food Chem ; 71(6): 3060-3067, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36720110

RESUMO

Sulfanilamide (SFL) is used to prevent infections in honeybees. However, many regulatory agencies prohibit or establish maximum levels of SFL residues in honey samples. Hence, we developed a low-cost and portable electrochemical method for SFL detection using a disposable device produced through 3D printing technology. In the proposed approach, the working electrode was printed using a conductive filament based on carbon black and polylactic acid and it was associated with square wave voltammetry (SWV). Under optimized SWV parameters, linear concentration ranges (1-10 µmol L-1 and 12.5-35.0 µmol L-1), a detection limit of 0.26 µmol L-1 (0.05 mg L-1), and suitable RSD values (2.4% for inter-electrode; n = 3) were achieved. The developed method was selective in relation to other antibiotics applied in honey samples, requiring only dilution in the electrolyte. The recovery values (85-120%) obtained by SWV were statistically similar (95% confidence level) to those obtained by HPLC, attesting to the accuracy of the analysis and the absence of matrix interference.


Assuntos
Mel , Fuligem , Animais , Fuligem/química , Sulfanilamida , Eletroquímica , Eletrodos , Técnicas Eletroquímicas , Carbono/química
19.
J Alzheimers Dis ; 90(1): 419-432, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36120784

RESUMO

BACKGROUND: The ATN scheme was proposed as an unbiased biological characterization of the Alzheimer's disease (AD) spectrum, grouping biomarkers into three categories: brain Amyloidosis-A, Tauopathy-T, Neurodegeneration-N. Although this scheme was mainly recommended for research, it is relevant for diagnosis. OBJECTIVE: To evaluate the ATN scheme performance in real-life cohorts reflecting the inflow of patients with cognitive complaints and different underlying disorders in general neurological centers. METHODS: We included patients (n = 1,128) from six centers with their core cerebrospinal fluid-AD biomarkers analyzed centrally. A was assessed through Aß42/Aß40, T through pTau-181, and N through tTau. Association between demographic features, clinical diagnosis at baseline/follow-up and ATN profiles was assessed. RESULTS: The prevalence of ATN categories was: A-T-N-: 28.3%; AD continuum (A + T-/+N-/+): 47.8%; non-AD (A- plus T or/and N+): 23.9%. ATN profiles prevalence was strongly influenced by age, showing differences according to gender, APOE genotype, and cognitive status. At baseline, 74.6% of patients classified as AD fell in the AD continuum, decreasing to 47.4% in mild cognitive impairment and 42.3% in other neurodegenerative conditions. At follow-up, 41% of patients changed diagnosis, and 92% of patients that changed to AD were classified within the AD continuum. A + was the best individual marker for predicting a final AD diagnosis, and the combinations A + T+ (irrespective of N) and A + T+N+ had the highest overall accuracy (83%). CONCLUSION: The ATN scheme is useful to guide AD diagnosis in real-life neurological centers settings. However, it shows a lack of accuracy for patients with other types of dementia. In such cases, the inclusion of other markers specific for non-AD proteinopathies could be an important aid to the differential diagnosis.


Assuntos
Doença de Alzheimer , Amiloidose , Disfunção Cognitiva , Humanos , Doença de Alzheimer/diagnóstico , Peptídeos beta-Amiloides , Proteínas tau , Disfunção Cognitiva/diagnóstico , Biomarcadores , Proteínas Amiloidogênicas , Fragmentos de Peptídeos
20.
World J Gastrointest Pharmacol Ther ; 13(4): 57-66, 2022 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-36051180

RESUMO

BACKGROUND: Low bone mineral density (BMD) is common in patients with inflammatory bowel disease. However, nutritional risk factors for low BMD in the ulcerative colitis (UC) population are still poorly understood. AIM: To investigate the association of anthropometric indicators and body composition with BMD in patients with UC. METHODS: This is a cross-sectional study on adult UC patients of both genders who were followed on an outpatient basis. A control group consisting of healthy volunteers, family members, and close people was also included. The nutritional indicators evaluated were body mass index (BMI), total body mass (TBM), waist circumference (WC), body fat in kg (BFkg), body fat in percentage (BF%), trunk BF (TBF), and also lean mass. Body composition and BMD assessments were performed by dual-energy X-ray absorptiometry. RESULTS: The sociodemographic characteristics of patients with UC (n = 68) were similar to those of healthy volunteers (n = 66) (P > 0.05). Most patients (97.0%) were in remission of the disease, 58.8% were eutrophic, 33.8% were overweight, 39.0% had high WC, and 67.6% had excess BF%. However, mean BMI, WC, BFkg, and TBF of UC patients were lower when compared to those of the control group (P < 0.05). Reduced BMD was present in 41.2% of patients with UC (38.2% with osteopenia and 2.9% with osteoporosis) and 3.0% in the control group (P < 0.001). UC patients with low BMD had lower BMI, TBM, and BFkg values than those with normal BMD (P < 0.05). Male patients were more likely to have low BMD (prevalence ratio [PR] = 1.86; 95% confidence interval [CI]: 1.07-3.26). Those with excess weight (PR = 0.43; 95%CI: 0.19-0.97) and high WC (PR = 0.44; 95%CI: 0.21-0.94) were less likely to have low BMD. CONCLUSION: Patients with UC in remission have a high prevalence of metabolic bone diseases. Body fat appears to protect against the development of low BMD in these patients.

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