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1.
Int J Biol Macromol ; : 133615, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38960221

RESUMO

Microencapsulation has emerged as a promising strategy to enhance the stability and protection of bioactive compounds. In this work, roasted mate tea was microencapsulated using 15 % maltodextrin and lasiodiplodan (0.5-1.25 %) as wall coating materials. The microcapsules were characterized for encapsulation efficiency, hygroscopicity, moisture, water activity, water solubility, dissolubility, scanning electron microscopy, FT-IR spectroscopy, thermal analysis, colorimetry, antioxidant activity, as well as quantification of phenolic compounds and caffeine. Microencapsulation yields ranged from 44.92 to 56.39 %, and the efficiency of encapsulation varied from 66.54 to 70.16 by increasing the lasiodiplodan concentration. FT-IR revealed phenolic acids, flavonoids, and polyphenolics. Minor color variations were observed among the samples. Thermal analysis demonstrated the microencapsulates exhibited good thermal stability with no degradation below 250 °C. Encapsulated samples showed high levels of bioactive compounds, suggesting that microencapsulation by spray-drying was a favorable process, where maltodextrin, a low-cost protective agent, when combined with the properties of lasiodiplodan, can be a good option for stabilizing mate extracts.

2.
Influenza Other Respir Viruses ; 18(5): e13307, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38798072

RESUMO

BACKGROUND: Seroepidemiological studies provide estimates of population-level immunity, prevalence/incidence of infections, and evaluation of vaccination programs. We assessed the seroprevalence of protective antibodies against influenza and evaluated the correlation of seroprevalence with the cumulative annual influenza incidence rate. METHODS: We conducted an annual repeated cross-sectional seroepidemiological survey, during June-August, from 2014 to 2019, in Portugal. A total of 4326 sera from all age groups, sex, and regions was tested by hemagglutination inhibition assay. Seroprevalence and geometric mean titers (GMT) of protective antibodies against influenza were assessed by age group, sex, and vaccine status (65+ years old). The association between summer annual seroprevalence and the difference of influenza incidence rates between one season and the previous one was measured by Pearson correlation coefficient (r). RESULTS: Significant differences in seroprevalence of protective antibodies against influenza were observed in the population. Higher seroprevalence and GMT for A(H1N1)pdm09 and A(H3N2) were observed in children (5-14); influenza B seroprevalence in adults 65+ was 1.6-4.4 times than in children (0-4). Vaccinated participants (65+) showed significant higher seroprevalence/GMT for influenza. A strong negative and significant correlation was found between seroprevalence and ILI incidence rate for A(H1N1)pdm09 in children between 5 and 14 (r = -0.84; 95% CI, -0.98 to -0.07); a weak negative correlation was observed for A(H3N2) and B/Yamagata (r ≤ -0.1). CONCLUSIONS: The study provides new insight into the anti-influenza antibodies seroprevalence measured in summer on the ILI incidence rate in the next season and the need for adjusted preventive health care measures to prevent influenza infection and transmission.


Assuntos
Anticorpos Antivirais , Influenza Humana , Humanos , Estudos Soroepidemiológicos , Estudos Transversais , Influenza Humana/epidemiologia , Influenza Humana/prevenção & controle , Influenza Humana/imunologia , Feminino , Masculino , Adulto , Incidência , Anticorpos Antivirais/sangue , Pré-Escolar , Criança , Pessoa de Meia-Idade , Adolescente , Adulto Jovem , Idoso , Portugal/epidemiologia , Lactente , Vacinas contra Influenza/imunologia , Vacinas contra Influenza/administração & dosagem , Vírus da Influenza A Subtipo H1N1/imunologia , Vírus da Influenza A Subtipo H3N2/imunologia , Testes de Inibição da Hemaglutinação , Vírus da Influenza B/imunologia , Estações do Ano , Recém-Nascido , Idoso de 80 Anos ou mais
4.
Front Plant Sci ; 15: 1351958, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38434432

RESUMO

Introduction: Precision monitoring maturity in climacteric fruits like tomato is crucial for minimising losses within the food supply chain and enhancing pre- and post-harvest production and utilisation. Objectives: This paper introduces an approach to analyse the precision maturation of tomato using hyperspectral tomography-like. Methods: A novel bi-directional spectral reconstruction method is presented, leveraging visible to near-infrared (Vis-NIR) information gathered from tomato spectra and their internal tissues (skin, pulp, and seeds). The study, encompassing 118 tomatoes at various maturation stages, employs a multi-block hierarchical principal component analysis combined with partial least squares for bi-directional reconstruction. The approach involves predicting internal tissue spectra by decomposing the overall tomato spectral information, creating a superset with eight latent variables for each tissue. The reverse process also utilises eight latent variables for reconstructing skin, pulp, and seed spectral data. Results: The reconstruction of the tomato spectra presents a mean absolute percentage error of 30.44 % and 5.37 %, 5.25 % and 6.42 % and Pearson's correlation coefficient of 0.85, 0.98, 0.99 and 0.99 for the skin, pulp and seed, respectively. Quality parameters, including soluble solid content (%), chlorophyll (a.u.), lycopene (a.u.), and puncture force (N), were assessed and modelled with PLS with the original and reconstructed datasets, presenting a range of R2 higher than 0.84 in the reconstructed dataset. An empirical demonstration of the tomato maturation in the internal tissues revealed the dynamic of the chlorophyll and lycopene in the different tissues during the maturation process. Conclusion: The proposed approach for inner tomato tissue spectral inference is highly reliable, provides early indications and is easy to operate. This study highlights the potential of Vis-NIR devices in precision fruit maturation assessment, surpassing conventional labour-intensive techniques in cost-effectiveness and efficiency. The implications of this advancement extend to various agronomic and food chain applications, promising substantial improvements in monitoring and enhancing fruit quality.

5.
Nat Prod Res ; 38(10): 1799-1805, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37292020

RESUMO

Phytochemical studies have shown extracts obtained from the aerial parts of Baccharis trimera (Less.) DC has antioxidant and antimicrobial activities and the potential to treat some diseases. This study investigated the phenolic compounds, antioxidant and antimicrobial activity, and phytochemical potential of B. trimera leaf extract obtained by decoction on ATCC standard bacterial strains and 23 swine clinical isolates. Water was used as an extraction solvent based on the principles of green chemistry and at a low cost. The decoction process resulted in an extract rich in phenolic compounds and a high capacity for scavenging DPPH and ABTS radicals. Phytochemical analysis of aqueous extracts was performed using HPLC-DAD, and high concentrations of chlorogenic, ferulic, caffeic, and cinnamic phenolic acids were found. Antimicrobial activity was observed against gram-negative bacteria. B. trimera aqueous extract may be a promising low-cost agent for prophylactic treatment against swine enteropathogens and contribute to reducing production costs.


Assuntos
Anti-Infecciosos , Baccharis , Cinamatos , Animais , Suínos , Antioxidantes/química , Extratos Vegetais/química , Baccharis/química , Compostos Fitoquímicos , Fenóis , Água , Anti-Infecciosos/análise
6.
Front Plant Sci ; 14: 1242201, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37662158

RESUMO

Early diagnosis of plant diseases is needed to promote sustainable plant protection strategies. Applied predictive modeling over hyperspectral spectroscopy (HS) data can be an effective, fast, cost-effective approach for improving plant disease diagnosis. This study aimed to investigate the potential of HS point-of-measurement (POM) data for in-situ, non-destructive diagnosis of tomato bacterial speck caused by Pseudomonas syringae pv. tomato (Pst), and bacterial spot, caused by Xanthomonas euvesicatoria (Xeu), on leaves (cv. cherry). Bacterial artificial infection was performed on tomato plants at the same phenological stage. A sensing system composed by a hyperspectral spectrometer, a transmission optical fiber bundle with a slitted probe and a white light source were used for spectral data acquisition, allowing the assessment of 3478 spectral points. An applied predictive classification model was developed, consisting of a normalizing pre-processing strategy allied with a Linear Discriminant Analysis (LDA) for reducing data dimensionality and a supervised machine learning algorithm (Support Vector Machine - SVM) for the classification task. The predicted model achieved classification accuracies of 100% and 74% for Pst and Xeu test set assessments, respectively, before symptom appearance. Model predictions were coherent with host-pathogen interactions mentioned in the literature (e.g., changes in photosynthetic pigment levels, production of bacterial-specific molecules, and activation of plants' defense mechanisms). Furthermore, these results were coherent with visual phenotyping inspection and PCR results. The reported outcomes support the application of spectral point measurements acquired in-vivo for plant disease diagnosis, aiming for more precise and eco-friendly phytosanitary approaches.

7.
Pathobiology ; 90(5): 333-343, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37040716

RESUMO

INTRODUCTION: Genomic variants of the human papillomavirus type 16 (HPV16) are thought to play differential roles in the susceptibility to head and neck squamous cell carcinomas (HNSCC) and its biological behaviour. This study aimed to establish the prevalence of HPV16 variants in an HNSCC cohort and associate them with clinical pathological characteristics and patient survival. METHODS: We retrieved samples and clinical data from 68 HNSCC patients. DNA samples were available from tumour biopsy at the time of the primary diagnosis. Targeted next-generation sequencing was used to obtain whole-genome sequences, and variants were established based on phylogenetic classification. RESULTS: 74% of samples clustered in lineage A, 5.7% in lineage B, 2.9% in lineage C, and 17.1% in lineage D. Comparative genome analysis revealed 243 single nucleotide variations. Of these, one hundred were previously reported, according to our systematic review. No significant associations with clinical pathological variables or patient survival were observed. The E6 amino acid variations E31G, L83V, and D25E and E7 N29S, associated with cervical cancer, were not observed, except for N29S in a single patient. CONCLUSION: These results provide a comprehensive genomic map of HPV16 in HSNCC, highlighting tissue-specific characteristics which will help design tailored therapies for cancer patients.

8.
Antibiotics (Basel) ; 12(3)2023 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-36978381

RESUMO

The growing concern about the emergence of increasingly antibiotic-r4esistant bacteria imposes the need to search and develop drugs to combat these microorganisms. This, combined with the search for low-cost synthesis methods, was the motivation for the elaboration of this work. Abietic acid present in the resin of Pinus elliotti var. elliotti was used to generate a sodium salt by salification. The synthesis route was low-cost, consisting of only two reaction steps at mild temperatures without toxic organic solvents, and eco-friendly and easy to conduct on an industrial scale. Sodium abietate (Na-C20H29O2) was characterized by mass spectrometry, infrared spectroscopy, elemental analysis, X-ray diffraction, scanning electron microscopy, and energy-dispersive spectroscopy. To perform the antimicrobial tests, the determination of minimum inhibitory concentration and the disk diffusion assay was performed. The results obtained showed that the salt Na abietate performed an antimicrobial action against the bacterial strains S. aureus, E. coli, L.monocytogenes, and S. enterica Typhimurium and the yeast C. albicans. The disk diffusion test showed a high inhibition potential against S. enterica compared to the standard antimicrobial tetracycline, as an inhibition index of 1.17 was found. For the other bacterial strains, the inhibition values were above 40%. The MIC test showed promising results in the inhibition of E. coli, L. monocytogenes, and C. albicans, indicating bacteriostatic activity against the first microorganism and bactericidal and fungicidal activities against the others. Therefore, the results showed the action of Na abietate as a possible effective antimicrobial drug, highlighting its sustainability within a circular economy.

9.
Sci Rep ; 12(1): 19384, 2022 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-36371484

RESUMO

The present study proposes the production of vinegars from pineapple processing residues as an eco-friendly strategy for adding value and economic strengthening of the production chain. Pineapple pulp and peel wines were produced and acetificated to vinegar by wild strains of acetic bacteria using Orlean's method (traditional system) followed by enrichment with leaf extract of Red-Jambo, Syzygium malaccense. Appreciable phenolic contents and antioxidant potential were found in pulp and peel vinegars with the added leaf extract. Catechin, epicatechin and caffeic, p-coumaric, ferulic, and gallic acids were the main phenolic compounds found in peel vinegar. The enrichment of the vinegar with the extract promoted an increase in the content of polyphenols (443.6-337.3 mg GAE/L) and antioxidant activity. Peel wines presented higher luminosity (L*) and higher saturation index (C*), and their color tended more toward yellow than pulp wines. Acetification reduced the saturation index (C*) and led to the intensification of the hue angle in the peels vinegar. Each type of pineapple vinegar produced showed biocidal activity against different bacteria and yeast, and the addition of leaf extract potentiated the antimicrobial activity of peel vinegar, especially against Staphalococcus aureus. The vinegars developed could find an attractive market niche in the food sector.


Assuntos
Ananas , Syzygium , Vinho , Ácido Acético/química , Ananas/química , Vinho/análise , Fenóis/química , Antioxidantes/química , Saccharomyces cerevisiae , Extratos Vegetais
10.
Molecules ; 27(19)2022 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-36235216

RESUMO

The search for less expensive and viable products is always one of the challenges for research development. Commonly, the synthesis of coordination compounds involves expensive ligands, through expensive and low-yield routes, in addition to generating toxic and unusable residues. In this work, the organic ligand used is derived from the resin of a reforestation tree, Pinus elliottii var. elliottii. The synthesis method used Pinus resin and an aqueous solution of vanadium(III) chloride at a temperature of 80 °C. The procedure does not involve organic solvents and does not generate toxic residues, thus imparting the complex formation reaction a green chemistry character. The synthesis resulted in an unprecedented oxovanadium(IV)-bis(abietate) complex, which was characterized by mass spectrometry (MS), chemical analysis (CHN), vibrational (FTIR) and electronic spectra (VISIBLE), X-ray diffraction (XRD), and thermal analysis (TG/DTA). Colorimetric studies were performed according to the CIELAB color space. The structural formula found, consisted of a complex containing two abietate ligands, [VO(C20H29O2)2]. The VO(IV)-bis(abietate) complex was applied against microorganisms and showed promising results in antibacterial and antifungal activity. The best result of inhibitory action was against the strains of Gram-positive bacteria S. aureus and L. monocytogenes, with minimum inhibitory concentration (MIC) values of 62.5 and 125 µmol L−1, respectively. For Gram-negative strains the results were 500 µmol L−1 for E. coli; and 1000 µmol L−1 for Salmonella enterica Typhimurium. Antifungal activity was performed against Candida albicans, where the MIC was 15.62 µmol L−1, and for C. tropicalis it was 62.5 µmol L−1. According to the MFC analysis, the complex presented, in addition to the fungistatic action, a fungicidal action, as there was no growth of fungi on the plates tested. The results found for the tests demonstrate that the VO(IV)-bis(abietate) complex has great potential as an antimicrobial and mainly antifungal agent. In this way, the pigmented ink with antimicrobial activity could be used in environments with a potential risk of contamination, preventing the spread of microorganisms harmful to health.


Assuntos
Anti-Infecciosos , Antifúngicos , Antibacterianos/química , Anti-Infecciosos/farmacologia , Antifúngicos/química , Candida albicans , Cloretos , Escherichia coli , Ligantes , Testes de Sensibilidade Microbiana , Solventes , Staphylococcus aureus , Vanádio/farmacologia
11.
Int J Mol Sci ; 23(20)2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-36293226

RESUMO

The study of human papillomavirus (HPV)-induced carcinogenesis uses multiple in vivo mouse models, one of which relies on the cytokeratin 14 gene promoter to drive the expression of all HPV early oncogenes. This study aimed to determine the HPV16 variant and sublineage present in the K14HPV16 mouse model. This information can be considered of great importance to further enhance this K14HPV16 model as an essential research tool and optimize its use for basic and translational studies. Our study evaluated HPV DNA from 17 samples isolated from 4 animals, both wild-type (n = 2) and HPV16-transgenic mice (n = 2). Total DNA was extracted from tissues and the detection of HPV16 was performed using a qPCR multiplex. HPV16-positive samples were subsequently whole-genome sequenced by next-generation sequencing techniques. The phylogenetic positioning clearly shows K14HPV16 samples clustering together in the sub-lineage A1 (NC001526.4). A comparative genome analysis of K14HPV16 samples revealed three mutations to the human papillomaviruses type 16 sublineage A1 representative strain. Knowledge of the HPV 16 variant is fundamental, and these findings will allow the rational use of this animal model to explore the role of the A1 sublineage in HPV-driven cancer.


Assuntos
Infecções por Papillomavirus , Neoplasias do Colo do Útero , Feminino , Humanos , Camundongos , Animais , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/genética , Queratina-14/genética , Filogenia , Neoplasias do Colo do Útero/genética , Papillomavirus Humano 16 , Papillomaviridae/genética , Carcinogênese/genética , Oncogenes
12.
Biomacromolecules ; 23(10): 4041-4052, 2022 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-36173245

RESUMO

Herpes simplex virus type 1 (HSV-1) is a persistent human pathogen, and the emergence of strains resistant to Acyclovir (ACV, reference drug) shows the urgency to develop new treatments. We report the antiherpetic mechanism of the action of lasiodiplodan (LAS-N, (1 → 6)-ß-d-glucan) and its sulfonated derivative (LAS-S3) in vitro and in vivo. LAS-S3 showed anti-HSV-1 action with high selectivity indices for HSV-1 KOS (88.1) and AR (189.2), sensitive and resistant to ACV, respectively. LAS-S3 inhibited >80% of HSV-1 infection in different treatment protocols (virucidal, adsorption inhibition, and post-adsorption effects), even at low doses, and showed a preventive effect and DNA and protein synthesis inhibition. The antiherpetic effect was confirmed in vivo by the cosmetic LAS-S3-CRÈME decreasing cutaneous lesions of HSV-1, including the AR strain. LAS-S3 possessed a broad-spectrum mechanism of action acting in the early and post-adsorption stages of HSV-1 infection, and LAS-S3-CRÈME is a potential antiherpetic candidate for patients infected by HSV-1-resistant strains.


Assuntos
Herpes Simples , Herpesvirus Humano 1 , Aciclovir/farmacologia , Aciclovir/uso terapêutico , Antivirais/farmacologia , Glucanos/farmacologia , Herpes Simples/tratamento farmacológico , Humanos
13.
Plants (Basel) ; 11(16)2022 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-36015456

RESUMO

Pseudomonas syringae pv. actinidiae (Psa) has been responsible for numerous epidemics of bacterial canker of kiwi (BCK), resulting in high losses in kiwi production worldwide. Current diagnostic approaches for this disease usually depend on visible signs of the infection (disease symptoms) to be present. Since these symptoms frequently manifest themselves in the middle to late stages of the infection process, the effectiveness of phytosanitary measures can be compromised. Hyperspectral spectroscopy has the potential to be an effective, non-invasive, rapid, cost-effective, high-throughput approach for improving BCK diagnostics. This study aimed to investigate the potential of hyperspectral UV-VIS reflectance for in-situ, non-destructive discrimination of bacterial canker on kiwi leaves. Spectral reflectance (325-1075 nm) of twenty plants were obtained with a handheld spectroradiometer in two commercial kiwi orchards located in Portugal, for 15 weeks, totaling 504 spectral measurements. Several modeling approaches based on continuous hyperspectral data or specific wavelengths, chosen by different feature selection algorithms, were tested to discriminate BCK on leaves. Spectral separability of asymptomatic and symptomatic leaves was observed in all multi-variate and machine learning models, including the FDA, GLM, PLS, and SVM methods. The combination of a stepwise forward variable selection approach using a support vector machine algorithm with a radial kernel and class weights was selected as the final model. Its overall accuracy was 85%, with a 0.70 kappa score and 0.84 F-measure. These results were coherent with leaves classified as asymptomatic or symptomatic by visual inspection. Overall, the findings herein reported support the implementation of spectral point measurements acquired in situ for crop disease diagnosis.

14.
Cancers (Basel) ; 14(5)2022 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-35267596

RESUMO

PIK3CA mutations are believed to contribute to the pathogenesis of human papillomavirus (HPV)-associated head and neck squamous cell carcinomas (HNSCC). This study aims to establish the frequency of PIK3CA mutations in a Portuguese HNSCC cohort and to determine their association with the HPV status and patient survival. A meta-analysis of scientific literature also revealed widely different mutation rates in cohorts from different world regions and a trend towards improved prognosis among patients with PIK3CA mutations. DNA samples were available from 95 patients diagnosed with HNSCC at the Portuguese Institute of Oncology in Lisbon between 2010 and 2019. HPV status was established based on viral DNA detected using real-time PCR. The evaluation of PIK3CA gene mutations was performed by real-time PCR for four mutations (H1047L; E542K, E545K, and E545D). Thirty-seven cases were found to harbour PIK3CA mutations (39%), with the E545D mutation (73%) more frequently detected. There were no significant associations between the mutational status and HPV status (74% WT and 68% MUT were HPV (+); p = 0.489) or overall survival (OS) (3-year OS: WT 54% and MUT 65%; p = 0.090). HPV status was the only factor significantly associated with both OS and disease-free survival (DFS), with HPV (+) patients having consistently better outcomes (3-year OS: HPV (+) 65% and HPV (-) 36%; p = 0.007; DFS HPV (+) 83% and HPV (-) 43%; p = 0.001). There was a statistically significant interaction effect between HPV status and PIK3CA mutation regarding DFS (Interaction test: p = 0.026). In HPV (+) patients, PIK3CA wild-type is associated with a significant 4.64 times increase in the hazard of recurrence or death (HR = 4.64; 95% CI 1.02-20.99; p = 0.047). Overall, PIK3CA gene mutations are present in a large number of patients and may help define patient subsets who can benefit from therapies targeting the PI3K pathway. The systematic assessment of PIK3CA gene mutations in HNSCC patients will require further methodological standardisation.

15.
Int J Mol Sci ; 22(20)2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34681671

RESUMO

The infection of mammalian cells by enveloped viruses is triggered by the interaction of viral envelope glycoproteins with the glycosaminoglycan, heparan sulfate. By mimicking this carbohydrate, some anionic polysaccharides can block this interaction and inhibit viral entry and infection. As heparan sulfate carries both carboxyl and sulfate groups, this work focused on the derivatization of a (1→3)(1→6)-ß-D-glucan, botryosphaeran, with these negatively-charged groups in an attempt to improve its antiviral activity. Carboxyl and sulfonate groups were introduced by carboxymethylation and sulfonylation reactions, respectively. Three derivatives with the same degree of carboxymethylation (0.9) and different degrees of sulfonation (0.1; 0.2; 0.4) were obtained. All derivatives were chemically characterized and evaluated for their antiviral activity against herpes (HSV-1, strains KOS and AR) and dengue (DENV-2) viruses. Carboxymethylated botryosphaeran did not inhibit the viruses, while all sulfonated-carboxymethylated derivatives were able to inhibit HSV-1. DENV-2 was inhibited only by one of these derivatives with an intermediate degree of sulfonation (0.2), demonstrating that the dengue virus is more resistant to anionic ß-D-glucans than the Herpes simplex virus. By comparison with a previous study on the antiviral activity of sulfonated botryosphaerans, we conclude that the presence of carboxymethyl groups might have a detrimental effect on antiviral activity.


Assuntos
Antivirais/farmacologia , Vírus da Dengue/efeitos dos fármacos , Herpesviridae/efeitos dos fármacos , Ácidos Sulfônicos/química , beta-Glucanas/química , Animais , Antivirais/química , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Vírus da Dengue/fisiologia , Glucanos/química , Glucanos/farmacologia , Herpesviridae/fisiologia , Metilação , Células Vero , Internalização do Vírus/efeitos dos fármacos , beta-Glucanas/farmacologia
16.
Sci Rep ; 11(1): 20550, 2021 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-34654845

RESUMO

Flour from Pereskia aculeata leaf and green banana were used as ingredients in the formulation of a cereal bar with added Lactobacillus acidophilus LA02-ID-1688. Encapsulation in a calcium-alginate hydrogel reinforced with magnesium hydroxide was used as a strategy to protect the probiotic cells under gastrointestinal conditions and to prolong shelf-life. The results are relevant especially for maintaining cell viability during shelf-life; a challenge for the food industry in relation to dry probiotic products. Encapsulation promoted the protection of probiotic cells in simulated gastric and intestinal conditions, allowing the maintenance of high viable cell counts (> 10 log CFU, colony forming unit). Encapsulation also contributed to cellular protection under extreme temperature conditions, with reductions of cell viability of < 1 logarithmic cycle when the capsules were subjected to 55ºC/10 min. Even at 75ºC/10 min, encapsulation protected the probiotic cells 3-times greater than the free-cells. The food bar proved to be rich in dietary fiber (19 g 100 g-1), lipids (12.63 g 100 g-1) and showed an appreciable protein content (5.44 g 100 g-1). A high viable probiotic cell count on storage over 120 days (12.54 log CFU) was observed, maintaining a probiotic survival rate > 90% and viability levels sufficient to promote health benefits.


Assuntos
Cactaceae/química , Encapsulamento de Células , Alimento Funcional/microbiologia , Lactobacillus acidophilus , Probióticos , Alginatos , Sobrevivência Celular , Chocolate , Alimento Funcional/análise , Hidrogéis , Hidróxido de Magnésio , Musa
17.
mSphere ; 6(4): e0024421, 2021 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-34319130

RESUMO

Recent studies have shown that persistent SARS-CoV-2 infections in immunocompromised patients can trigger the accumulation of an unusual high number of mutations with potential relevance at both biological and epidemiological levels. Here, we report a case of an immunocompromised patient (non-Hodgkin lymphoma patient under immunosuppressive therapy) with a persistent SARS-CoV-2 infection (marked by intermittent positivity) over at least 6 months. Viral genome sequencing was performed at days 1, 164, and 171 to evaluate SARS-CoV-2 evolution. Among the 15 single-nucleotide polymorphisms (SNPs) (11 leading to amino acid alterations) and 3 deletions accumulated during this long-term infection, four amino acid changes (V3G, S50L, N87S, and A222V) and two deletions (18-30del and 141-144del) occurred in the virus Spike protein. Although no convalescent plasma therapy was administered, some of the detected mutations have been independently reported in other chronically infected individuals, which supports a scenario of convergent adaptive evolution. This study shows that it is of the utmost relevance to monitor the SARS-CoV-2 evolution in immunocompromised individuals, not only to identify novel potentially adaptive mutations, but also to mitigate the risk of introducing "hyper-evolved" variants in the community. IMPORTANCE Tracking the within-patient evolution of SARS-CoV-2 is key to understanding how this pandemic virus shapes its genome toward immune evasion and survival. In the present study, by monitoring a long-term COVID-19 immunocompromised patient, we observed the concurrent emergence of mutations potentially associated with immune evasion and/or enhanced transmission, mostly targeting the SARS-CoV-2 key host-interacting protein and antigen. These findings show that the frequent oscillation in the immune status in immunocompromised individuals can trigger an accelerated virus evolution, thus consolidating this study model as an accelerated pathway to better understand SARS-CoV-2 adaptive traits and anticipate the emergence of variants of concern.


Assuntos
COVID-19/imunologia , Evasão da Resposta Imune/imunologia , Hospedeiro Imunocomprometido/imunologia , Linfoma não Hodgkin/imunologia , SARS-CoV-2/imunologia , Aminoácidos/genética , Aminoácidos/imunologia , Animais , COVID-19/virologia , Linhagem Celular , Chlorocebus aethiops , Feminino , Genoma Viral/genética , Genoma Viral/imunologia , Humanos , Evasão da Resposta Imune/genética , Imunização Passiva/métodos , Linfoma não Hodgkin/virologia , Pessoa de Meia-Idade , Mutação/genética , Mutação/imunologia , Pandemias/prevenção & controle , SARS-CoV-2/genética , Células Vero , Replicação Viral/genética , Replicação Viral/imunologia
18.
Sensors (Basel) ; 21(10)2021 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-34065568

RESUMO

The development of robotic solutions for agriculture requires advanced perception capabilities that can work reliably in any crop stage. For example, to automatise the tomato harvesting process in greenhouses, the visual perception system needs to detect the tomato in any life cycle stage (flower to the ripe tomato). The state-of-the-art for visual tomato detection focuses mainly on ripe tomato, which has a distinctive colour from the background. This paper contributes with an annotated visual dataset of green and reddish tomatoes. This kind of dataset is uncommon and not available for research purposes. This will enable further developments in edge artificial intelligence for in situ and in real-time visual tomato detection required for the development of harvesting robots. Considering this dataset, five deep learning models were selected, trained and benchmarked to detect green and reddish tomatoes grown in greenhouses. Considering our robotic platform specifications, only the Single-Shot MultiBox Detector (SSD) and YOLO architectures were considered. The results proved that the system can detect green and reddish tomatoes, even those occluded by leaves. SSD MobileNet v2 had the best performance when compared against SSD Inception v2, SSD ResNet 50, SSD ResNet 101 and YOLOv4 Tiny, reaching an F1-score of 66.15%, an mAP of 51.46% and an inference time of 16.44ms with the NVIDIA Turing Architecture platform, an NVIDIA Tesla T4, with 12 GB. YOLOv4 Tiny also had impressive results, mainly concerning inferring times of about 5 ms.

19.
Int J Biol Macromol ; 183: 316-330, 2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-33930443

RESUMO

A hydrogel containing exocellular (1 → 6)-ß-D-glucan (lasiodiplodan, LAS) was developed and its wound healing potential was evaluated. ß-Glucans have attracted much interest by the cosmetic industry sector because of their bioactive and functional properties and in promoting skin health. In the present work an ß-glucan was studied as a healing biomaterial that has not hitherto been reported in the scientific literature. LAS produced by the ascomycete Lasiodiplodia theobromae MMPI was used in the formulation of a healing hydrogel. Physicochemical and microbiological quality parameters, antioxidant potential and stability of the formulation was evaluated. FTIR, thermal analysis and SEM techniques were also employed in the characterization. Wistar rats were used as a biological model to investigate the wound healing potential. Histological analyses of cutaneous tissue from the dorsal region were conducted after 4, 7, 10 and 14 days of treatment, and evaluated re-epithelialization, cell proliferation and collagen production. Physicochemical stability, microbiological quality and antioxidant potential, especially in relation to its ability to scavenge hydroxyl radicals were found. The hydrogel stimulated cell re-epithelialization and proliferation during all days of the treatment, and stimulated an increase of collagen fibers. Lasiodiplodan showed immunomodulatory activity in wound healing and this biomacromolecule could be an alternative compound in wound care.


Assuntos
Colágeno/química , Glucanos/química , Hidrogéis/química , Hidrogéis/farmacologia , Polissacarídeos/química , Cicatrização/efeitos dos fármacos , Animais , Ratos
20.
Int J Mol Sci ; 22(5)2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33669021

RESUMO

The expression of p16 is a good surrogate of human papillomavirus (HPV) infection in HPV-associated cancers. The significance of p16 expression, HPV genotype and genera in the outcome of patients with HPV-associated cervical cancer (CC) is unclear. Our aim is to ascertain the prognostic significance of these factors. Data from 348 patients (median age: 47.5 years old) with CC, diagnosed in two referral centers, were retrospectively collected. Advanced disease (FIGO2018 IB2-IV) was present in 68% of patients. A single HPV genotype was identified in 82.8% of patients. The most common HPVs were HPV16 (69%) and HPV18 (14%). HPV genera reflected this distribution. HPV16 tumors presented at an earlier stage. P16 was negative in 18 cases (5.2%), 83.3% of which were squamous cell carcinomas. These cases occurred in older patients who tended to have advanced disease. In the univariate analysis, HPV16 (HR: 0.58; p = 0.0198), α-9 genera (HR: 0.37; p = 0.0106) and p16 overexpression (HR: 0.54; p = 0.032) were associated with better survival. HPV16 (HR: 0.63; p = 0.0174) and α-9 genera (HR: 0.57; p = 0.0286) were associated with less relapse. In the multivariate analysis, only the International Federation of Gynecology and Obstetrics (FIGO) stage retained an independent prognostic value. HPV16, α-9 genera and p16 overexpression were associated with better survival, although not as independent prognostic factors. Patients with p16-negative HPV-associated CC were older, presented with advanced disease and had worse prognosis.


Assuntos
Adenocarcinoma/metabolismo , Carcinoma de Células Escamosas/metabolismo , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Papillomaviridae/genética , Infecções por Papillomavirus/virologia , Neoplasias do Colo do Útero/metabolismo , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Adenocarcinoma/virologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/virologia , Estudos de Coortes , Feminino , Papillomavirus Humano 16/genética , Papillomavirus Humano 18/genética , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Estudos Retrospectivos , Centros de Atenção Terciária , Regulação para Cima , Neoplasias do Colo do Útero/mortalidade , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/virologia , Adulto Jovem
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