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1.
Front Nutr ; 11: 1340121, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38628271

RESUMO

Consumers are increasingly interested in food products with high nutritional value and health benefits. For instance, fish consumption is linked with diverse positive health benefits and the prevention of certain widespread disorders, such as obesity, metabolic syndrome, or cardiovascular diseases. These benefits have been attributed to its excellent nutritional value (large amounts of high-quality fatty acids, proteins, vitamins, and minerals) and bioactive compounds, while being relatively low-caloric. Atlantic bluefin tuna (Thunnus tynnus) is one of the most consumed species worldwide, motivated by its good nutritional and organoleptic characteristics. Recently, some organizations have proposed limitations on its consumption due to the presence of contaminants, mainly heavy metals such as mercury. However, several studies have reported that most specimens hold lower levels of contaminants than the established limits and that their richness in selenium effectively limits the contaminants' bioaccessibility in the human body. Considering this situation, this study aims to provide baseline data about the nutritional composition and the latest evidence regarding the beneficial effects of Atlantic bluefin tuna consumption. A review of the risk-benefit ratio was also conducted to evaluate the safety of its consumption, considering the current suggested limitations to this species' consumption.

2.
Plant Biol (Stuttg) ; 26(4): 612-620, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38634401

RESUMO

Most Aristolochiaceae species studied so far are from temperate regions, bearing self-compatible protogynous trap flowers. Although self-incompatibility has been suggested for tropical species, the causes of self-sterility in this family remain unknown. To fill this gap, we studied the pollination of the tropical Aristolochia esperanzae, including the physical and physiological anti-selfing mechanisms. Floral visitors trapped inside flowers were collected to determine the pollinators. Protogyny was characterized by observing the temporal expression of sexual phases and stigmatic receptivity tests. The breeding system was investigated using hand-pollination treatments. Pollen tube growth was observed using epifluorescence to identify the self-incompatibility mechanism. Flies were the most frequent visitors found inside A. esperanzae trap flowers, with individuals from the family Ulidiidae being potential pollinators since they carried pollen. The characteristic flower odour and presence of larvae indicate that A. esperanzae deceives flies through oviposition-site mimicry. Although this species showed incomplete protogyny, stigmatic receptivity decreased during the male phase, avoiding self-pollination. Fruits developed only after cross- and open pollination, indicating that the population is non-autonomous, non-apomictic, and self-sterile. This occurred through a delay in the growth of geitonogamous pollen tubes to the ovary and lower ovule penetration, indicating a late-acting self-incompatibility mechanism. Our findings expand the number of families in which late-acting self-incompatibility has been reported, demonstrating that it is more widespread than previously thought, especially when considering less-studied tropical species among the basal angiosperms.


Assuntos
Aristolochia , Flores , Polinização , Polinização/fisiologia , Flores/fisiologia , Aristolochia/fisiologia , Animais , Autoincompatibilidade em Angiospermas/fisiologia , Tubo Polínico/fisiologia , Tubo Polínico/crescimento & desenvolvimento , Frutas/fisiologia , Frutas/crescimento & desenvolvimento , Pólen/fisiologia , Dípteros/fisiologia
3.
Plant Biol (Stuttg) ; 26(3): 421-426, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38315474

RESUMO

Longer stigmas in short-styled morphs of distylous plants have been considered an adaptive characteristic that increases intermorph pollen deposition. The greater pollen deposition in short-styled stigmas may be a by-product of their longer length, making deposition effectiveness comparison between morphs unfeasible. Thus, investigating which morph has the relatively most efficient stigma (i.e., pollen deposition per unit length) can boost our understanding of the adaptive significance of longer stigmas. Here, we compared pollen deposition between morphs relative to stigma length and assessed whether short-styled stigmas are more, less, or equally effective in receiving pollen grains per unit length. We reviewed the literature to characterize the extent of sigma length differences between morphs using the two most speciose distylous genera as model systems: Palicourea and Psychotria (Rubiaceae). Then, we conducted a between-morph comparison of raw and relative pollen depositions in a Palicourea rigida population. We confirmed that short-styled stigmas were longer than long-styled stigmas in both Palicourea (194.31% longer) and Psychotria (52.59% longer) flowers. Furthermore, in the focal Pal. rigida, although short-styled stigmas were 268.04% longer and received 97.04% more pollen grains than long-styled stigmas, the relative pollen deposition had a reverse pattern, with short-styled stigmas being two-times less efficient in receiving pollen. Our results indicate that the longer length of the short-styled stigmas may have a compensatory effect, increasing the chances of pollen grains reaching the stigma and probably maintaining disassortative intermorph pollination in distylous plants.


Assuntos
Polinização , Rubiaceae , Pólen , Flores
4.
Braz J Biol ; 84: e277637, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38422287

RESUMO

Fish processing provides waste of around 50.0% to 70.0% of the animal's initial weight, especially the skin. Thus, this residue contains the by-product that allows biopolymers to be obtained, highlighting collagen, which can be widely used in different areas. The present study aimed to evaluate the yield of collagen extracted from peacock bass Cichla monoculus skin and to characterize them physicochemically. Twenty-five peacock bass with an average weight of 646 ± 175 g were used. The skin samples were removed by manual filleting and weighed, with an average yield of 3.7%. Subsequently, such models were analyzed for chemical composition, showing 61.8% for moisture, 29.3% for crude protein, 1.5% for ash, 6.3% for total lipids, and 1.2% for non-nitrogenous extract (NNE). Acid-soluble collagen (ASC) presented an average yield of 8.2%, presenting in its analysis of centesimal composition 12.5% ​​of moisture, 82.6% of crude protein, 1.1% of ash, 2.6% of total lipids, and 1.2% NNE. The skin and collagen extracted from the tucunaré skin have technological potential for use in the preparation of products, adding value to these by-products from fish processing.


Assuntos
Ciclídeos , Animais , Colágeno , Lipídeos
5.
Crit Rev Food Sci Nutr ; : 1-20, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38251987

RESUMO

Health-promoting foods have become increasingly popular due to intensified consumer interest and awareness of illnesses. There is a global market for apple fruits, which are affordable, nutritious, tasty, and produced in large quantities for direct consumption as well as food processing to make derived products. The food matrix of apples is suitable for fermentation, besides containing a high amount of phenolics and polyphenols. Fermentation of apples is one of the most common methods of preserving apple fruit and its byproducts. With different fermentation techniques, apple fruit can be used to make a wide range of products, such as fermented apple juice, cider, liqueurs, apple cider, apple vinegar and fermented apple solids, because it is not only a low-cost and simple method of processing the fruit, but it can also sometimes increase the bioavailability of nutrients and the levels of components that can improve health and sensory quality. To understand the health benefits of food products and how the fermentation process impacts polyphenols, it is also crucial to observe the effects of digestion on polyphenol bioaccessibility. Polyphenolic profile changes can be observed via both in vitro and in vivo digestion methods; however, in vitro digestion methods have the advantage of observing every step of gastrointestinal track effects and have less cost as well. In this review, the polyphenolic profile, processing impact, and bioaccessibility of apple-fermented products is assessed, with most available studies showing polyphenol profiles and bioaccessibility in apple varieties and fermented apple products.

6.
Plant Biol (Stuttg) ; 26(1): 34-40, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37856560

RESUMO

In many families, plants undergo floral resupination by twisting through approximately 180° during floral development so that the flower is effectively positioned upside down. In most orchids, resupination results in the median petal (i.e., the labellum) becoming lowermost, which plays a crucial role in pollination by serving as a landing platform or as a trapping device, or both. Incomplete resupination is predicted to lead to reduced pollination, although tests of this assumption are still lacking. We investigated the effect of resupination using Phragmipedium vittatum, a rare lady's slipper orchid whose specialized labellum forms a trapping device. First, we surveyed the natural occurrence of incomplete resupination. Then we manipulated flowers into non- (≈0°), half- (≈90°), and fully resupinate (≈180°) positions to test the effect of orientation on pollen smear removal and deposition by pollinators (female hoverflies). We found that ca. 10% of flowers in the natural population were not fully resupinate, being either non- (upward, 0-60°) or half-resupinate (sideward, 60-120°). The change in orientation prevented the effectiveness of pollination by hoverflies since no pollen smear removal or deposition were found in flowers from non- and half-resupinate treatments. Although these flowers still attracted hoverflies, they were not trapped effectively. As this orchid is incapable of autonomous self-pollination, flowers that do not resupinate fail to set fruits. These results highlight the importance of correct floral orientation provided by resupination to ensure pollination in orchids and other resupinate flowers.


Assuntos
Orchidaceae , Polinização , Humanos , Flores , Pólen , Frutas
7.
Pulmonology ; 2023 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-37903685

RESUMO

OBJECTIVES: To investigate smoking trajectories and their association with pulmonary function (PF) and respiratory symptoms at age 22. METHODS: Data from a population-based cohort study of 3350 individuals and their spirometries were analysed. The outcomes were: forced expiratory volume in the first second (FEV1), forced vital capacity (FVC), forced expiratory flow at the mid expiratory phase (FEF25-75 %), FEV1/FVC and FEF25-75/FVC ratio. Smoking data were collected at perinatal follow-up (gestational exposure) and 15, 18 and 22 years. Group-based trajectory model was applied. RESULTS: Four groups were identified: no exposure (NE), gestational (GE), gestational and adulthood (GAE) and continuous (CE) exposure. Both CE and GAE trajectories were associated with lower values of FEV1/FVC (-1.77pp; p = 0.01 and -1.58 pp; p<0.001 respectively) and FEF25-75/FVC ratio (-7.27pp; p = 0.019 and -6.04pp; p<0.001 respectively) compared to the NE trajectory. Lower FEV1 and FEF25-75 % values were also related to the GAE trajectory (-68 ml; p = 0.03 and -253 ml/s;p<0.001 respectively). Compared to those who never smoked, individuals who smoked 10 or more cigarettes daily presented a reduction in the FEV1/FVC ratio by 1.37pp (p<0.001), FEF25-75 % by 126 ml (p = 0.012) and FEF25-75 %/FVC ratio by 3.62pp (p = 0.011). CE trajectory showed higher odds of wheezing (OR 4.14; p<0.001) and cough (OR 2.39; p = 0.002) compared to the non-exposed group. CONCLUSIONS: The in-uterus exposure to maternal smoking reduces PF later in life. However, the perpetuation of smoking behaviour throughout adolescence and early adulthood is determinant for PF main reduction and the emergence of respiratory-related symptoms.

8.
Public Health ; 223: 162-170, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37659322

RESUMO

OBJECTIVES: The aims of this article were to analyse the burden of NCDs and their RFs in the Mercosur countries between 1990 and 2019 and to project mortality trends for 2030. STUDY DESIGN: Epidemiological study of time series. METHODS: The present study used data from the Global Burden of Disease study. The absolute number of deaths, mortality rates, disability-adjusted life years, years of life lost, years lived with disability and the burden of premature mortality by NCD attributable to the RFs were evaluated. Projections were made up to 2030. Age-standardised rates were used to draw comparisons by years and by countries. The analysis was conducted using the RStudio software. RESULTS: Between 1990 and 2019, a decrease was found in the premature mortality rates caused by NCDs in all the countries, except for Paraguay, which remained stable. When analysing premature mortality rates due to NCDs up to 2030, it was predicted that none of the countries would achieve the sustainable development goal of a one-third reduction in premature mortality by NCDs. Regarding the impacts of the RFs for NCDs, smoking, dietary risks, high blood pressure (BP) and high body mass index (BMI) were the main risks attributable to premature deaths due to NCDs. CONCLUSIONS: The results showed that mortality rates are declining in Mercosur countries; however, none of the countries are predicted to achieve the sustainable development goal of a one-third reduction in mortality due to NCDs by 2030. In addition to access to adequate treatment, progress is required in public regulation actions to reduce RFs, such as smoking, dietary risks, high BP and high BMI.


Assuntos
Hipertensão , Doenças não Transmissíveis , Humanos , Desenvolvimento Sustentável , Saúde Global , Mortalidade Prematura , Fumar , Carga Global da Doença , Fatores de Risco , Anos de Vida Ajustados por Qualidade de Vida
9.
Braz J Biol ; 83: e271339, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37729210

RESUMO

Uncaria tomentosa is a plant native to the Amazon that has immunomodulatory and antitumor properties due to the alkaloids found in the plant, being able to modify the immune response by potentiating or suspending the action of cytokines secreted by macrophages that induce the immune response, either by the classical route (M1) or through the alternative route (M2). Macrophages activated by M1 convert L-arginine into L-citrulline and nitric oxide (NO), whereas macrophages activated by the M2 pathway use the enzymatic activity of arginase to convert the same substrate into L-ornithine and urea. The aim of this work was to evaluate the immunostimulating activity of the crude hydroalcoholic extract from the bark of the U. tomentosa stem in RAW 264.7 macrophages. Concentrations of 0.2, 0.1 and 0.05 mg/mL of U. tomentosa extract associated with LPS, INF-γ and IL-4 inducers were tested by determining NO production and arginase enzyme activity. Nitric oxide production was enhanced by the extract when associated with LPS and LPS + INF-γ inducers. In the activity of the arginase enzyme, the extract decreased the stimulation of IL-4 on the enzyme, mainly at 0.2 mg/mL concentration. Therefore, it is concluded that the crude hydroalcoholic extract of the stem bark of U. tomentosa in RAW 264.7 cells, at a concentration of 0.2 mg/mL, showed considerable pro-inflammatory activity.


Assuntos
Unha-de-Gato , Arginase , Interleucina-4 , Lipopolissacarídeos/farmacologia , Óxido Nítrico , Macrófagos , Extratos Vegetais/farmacologia
10.
Braz J Med Biol Res ; 56: e12647, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37585915

RESUMO

DiGeorge syndrome is a disorder caused by a microdeletion on the long arm of chromosome 22. Approximately 1% of patients diagnosed with DiGeorge syndrome may have an absence of a functional thymus, which characterizes the complete form of the syndrome. These patients require urgent treatment to reconstitute T cell immunity. Thymus transplantation is a promising investigational procedure for reconstitution of thymic function in infants with congenital athymia. Here, we demonstrate a possible optimization of the preparation of thymus slices for transplantation through prior depletion of thymocytes and leukocyte cell lineages followed by cryopreservation with cryoprotective media (5% dextran FP 40, 5% Me2SO, and 5% FBS) while preserving tissue architecture. Thymus fragments were stored in liquid nitrogen at -196°C for 30 days or one year. The tissue architecture of the fragments was preserved, including the distinction between medullary thymic epithelial cells (TECs), cortical TECs, and Hassall bodies. Moreover, depleted thymus fragments cryopreserved for one year were recolonized by intrathymic injections of 3×106 thymocytes per mL, demonstrating the capability of these fragments to support T cell development. Thus, this technique opens up the possibility of freezing and storing large volumes of thymus tissue for immediate transplantation into patients with DiGeorge syndrome or atypical (Omenn-like) phenotype.


Assuntos
Síndrome de DiGeorge , Síndromes de Imunodeficiência , Humanos , Timócitos , Síndrome de DiGeorge/terapia , Timo , Células Epiteliais
11.
Exp Oncol ; 45(1): 107-119, 2023 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-37417276

RESUMO

BACKGROUND: Skeletal muscle wasting is a common phenotypic feature of several types of cancer, and it is associated with functional impairment, respiratory complications, and fatigue. However, equivocal evidence remains regarding the impact of cancer-induced muscle wasting on the different fiber types. AIM: The aim of this study was to investigate the impact of urothelial carcinoma induced in mice on the histomorphometric features and collagen deposition in different skeletal muscles. MATERIALS AND METHODS: Thirteen ICR (CD1) male mice were randomly assigned into two groups: exposed to 0.05% N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN) in drinking water for 12 weeks, plus 8 weeks of tap water (BBN, n = 8) or with access to tap water for 20 weeks (CONT, n = 5). Tibialis anterior, soleus, and diaphragm muscles were collected from all animals. For cross-sectional area and myonuclear domain analysis, muscle sections were stained with hematoxylin and eosin, and for collagen deposition assessment, muscle sections were stained with picrosirius red. RESULTS: All animals from the BBN group developed urothelial preneoplastic and neoplastic lesions, and the tibialis anterior from these animals presented a reduced cross-sectional area (p < 0.001), with a decreased proportion of fibers with a higher cross-sectional area, increased collagen deposition (p = 0.017), and higher myonuclear domain (p = 0.031). BBN mice also showed a higher myonuclear domain in the diaphragm (p = 0.015). CONCLUSION: Urothelial carcinoma induced muscle wasting of the tibialis anterior, expressed by a decreased cross-sectional area, higher infiltration of fibrotic tissue, and increased myonuclear domain, which also increased in the diaphragm, suggesting that fast glycolytic muscle fibers are more susceptible to be affected by cancer development.


Assuntos
Carcinoma de Células de Transição , Neoplasias da Bexiga Urinária , Camundongos , Masculino , Animais , Carcinoma de Células de Transição/patologia , Neoplasias da Bexiga Urinária/complicações , Neoplasias da Bexiga Urinária/patologia , Camundongos Endogâmicos ICR , Músculo Esquelético/patologia , Músculo Esquelético/fisiologia , Fibras Musculares de Contração Rápida/patologia , Atrofia Muscular/etiologia , Atrofia Muscular/patologia
12.
Eur Rev Med Pharmacol Sci ; 27(3 Suppl): 141-146, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37129325

RESUMO

BACKGROUND: Horizontal atrophic ridges need a regenerative procedure for implant positioning and fixed rehabilitation. Cone Morse taper implants are characterized by the intimate fitting of the prosthetic interface with the absence of microgaps and micromovements of the interfaces. The aim of this case report was to evaluate the clinical outcome of Cone Morse implant design in split crest augmentation treatment. CASE REPORT: A female patient with partial edentulism of atrophic posterior maxilla was treated for split crest procedure and implant-supported rehabilitation. A full-thickness flap was elevated, and horizontal and vertical osteotomic lines were produced with piezoelectric device. A total of 4 Cone Morse Taper implants (Universal III, Implacil de Bortoli, Brasil) were positioned and the site was grafted with bone substitute and covered by a heterologous membrane. CONCLUSIONS: A complete healing of the surgical site was evident at the follow-up with no evidence of bone resorption. No radiolucency or inflammatory aspects of the treated site were evident in the radiographic control. Simultaneous Cone Morse implants positioning with split crest technique seems to be a promising treatment for posterior maxillary rehabilitation of atrophic edentulous ridges.


Assuntos
Reabsorção Óssea , Substitutos Ósseos , Implantes Dentários , Humanos , Feminino , Maxila/cirurgia , Brasil , Implantação Dentária Endóssea , Prótese Dentária Fixada por Implante , Resultado do Tratamento , Seguimentos
13.
Plant Biol (Stuttg) ; 25(3): 457-467, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36728131

RESUMO

Polyploidy and whole genome duplication are major evolutionary drivers in plants. Climate variations during the Pleistocene have influenced distribution and range expansion worldwide. Similar trends have been reported for Cerrado plants, but no attempt has been made to link phylogeography with ploidy and breeding changes. Thus, we aimed to (i) assess ploidy and genome size of Eriotheca estevesiae Carv.-Sobr., and compare it with E. pubescens (Mart.) Schott & Endl. (Both included into the Eriotheca Stellate Trichome Species Complex - ESTSC). (ii) Subsequently, we investigated their phylogeography to see whether genetic structure and range expansion trends were similar to those previously described for the Cerrado biome. Finally (iii), we discuss whether ESTSC phylogeographic patterns could be associated with geographic parthenogenesis processes. Common cytogenetic techniques and flow cytometry were used to confirm chromosome number and genome size of E. estevesiae. We used three cpDNA regions to analyse 14 ESTSC Cerrado populations, for which we also obtained ploidy level and breeding information. We investigated haplotype diversity, population structure and tested neutrality, aiming to reconstruct phylogeographic scenarios. We found three ploidy levels and eight cpDNA haplotypes in ESTSC, one shared by most populations. Haplotype and ploidy distribution corroborated that E. pubescens, the widely distributed polyploid and apomictic species, may have originated from northern diploid and probably sexual E. estevesiae. Matrilinear cpDNA links support the idea that apomixis and polyploidy in ESTSC may have allowed range expansion during the Pleistocene, in a process analogous to the geographic parthenogenesis described elsewhere.


Assuntos
Apomixia , Filogeografia , Árvores/genética , Pradaria , Sementes , Melhoramento Vegetal , Poliploidia , DNA de Cloroplastos/genética , Variação Genética
14.
Pulmonology ; 29 Suppl 4: S44-S53, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34629326

RESUMO

INTRODUCTION: The diagnosis and severity assessment of COPD relies on spirometry, and in particular the FEV1. However, it has been proposed that hyperinflation and air-trapping are better predictors of exercise capacity and mortality than the FEV1. RESEARCH: QUESTION: Does static hyperinflation predict exercise capacity? METHODS: We conducted an observational prospective study. Patients with COPD referred to the lung function laboratory were consecutively recruited. Patients with hyperinflation (the experimental group) were compared to patients without hyperinflation (the control group). The sample sizes were determined assuming an effect size of 0.5 and a power of 0.80. RESULTS: We recruited 124 participants, of whom 87% were male, the mean age was 66.1 ± 8.8 years. 67% were symptomatic (GOLD B or D). Airflow limitation was moderate to severe in the majority of patients (median FEV1 47%, IQR 38-65%) and 43% of patients had static hyperinflation. The median 6MWD was 479 meters (404-510) and peak workload in CPET was 64 watts (46-88) with peak VO2 1.12 L/min, 0.89-1.31 L/min. Patients with lower FEV1, DLCO and IC/TLC and higher RV/TLC had reduced exercise capacity in both 6MWT and CPET, measured as lower distance, greater desaturation and ∆Borg dyspnoea, and reduced workload, peak VO2 and peak VE and higher desaturation and ventilatory limitation (VE/MVV). An IC/TLC < 0.33 predicted reduced exercise performance (peak O2 <60%). Dyspnoea assessed by mMRC and QoL measured by CAT and CCQ were also worse in the hyperinflation in COPD patients. CONCLUSION: In COPD patients, IC/TLC and RV/TLC are valuable predictors of exercise performance in both 6MWT and CPET and PRO.


Assuntos
Doença Pulmonar Obstrutiva Crônica , Humanos , Masculino , Pessoa de Meia-Idade , Idoso , Feminino , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Estudos Prospectivos , Tolerância ao Exercício , Qualidade de Vida , Dispneia/diagnóstico , Dispneia/etiologia
15.
Crit Rev Food Sci Nutr ; 63(13): 1901-1929, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-34463176

RESUMO

Nowadays, consumers are increasingly aware of the relationship between diet and health, showing a greater preference of products from natural origin. In the last decade, seaweeds have outlined as one of the natural sources with more potential to obtain bioactive carbohydrates. Numerous seaweed polysaccharides have aroused the interest of the scientific community, due to their biological activities and their high potential on biomedical, functional food and technological applications. To obtain polysaccharides from seaweeds, it is necessary to find methodologies that improve both yield and quality and that they are profitable. Nowadays, environmentally friendly extraction technologies are a viable alternative to conventional methods for obtaining these products, providing several advantages like reduced number of solvents, energy and time. On the other hand, chemical modification of their structure is a useful approach to improve their solubility and biological properties, and thus enhance the extent of their potential applications since some uses of polysaccharides are still limited. The present review aimed to compile current information about the most relevant seaweed polysaccharides, available extraction and modification methods, as well as a summary of their biological activities, to evaluate knowledge gaps and future trends for the industrial applications of these compounds.Key teaching pointsStructure and biological functions of main seaweed polysaccharides.Emerging extraction methods for sulfate polysaccharides.Chemical modification of seaweeds polysaccharides.Potential industrial applications of seaweed polysaccharides.Biological activities, knowledge gaps and future trends of seaweed polysaccharides.


Assuntos
Produtos Biológicos , Polissacarídeos , Alga Marinha , Alga Marinha/química , Polissacarídeos/análise , Polissacarídeos/química , Alimento Funcional , Alginatos/análise , Alginatos/química , Ágar/análise , Ágar/química , Carragenina/análise , Carragenina/química , Fracionamento Químico/métodos , Estrutura Molecular
16.
J Anal Toxicol ; 47(3): 227-235, 2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-36124733

RESUMO

The use of new psychoactive substances has been increasing and constitutes a social and public health problem, and hence, toxicological analysis has become of utmost importance for the detection of such substances. In this article, we present the development and full validation of a simple, user and environmentally friendly, cheap and suitable method for the determination of ketamine and its main metabolite norketamine in hair samples. The procedure included using a miniaturized procedure-microextraction by packed sorbent with mixed-mode sorbent-for sample clean-up. Organic solvents use was minimal, and it was possible to obtain a linear method (0.05-10 ng/mg for both analytes). The extraction efficiency ranged from 32 to 61%, which did not impair sensitivity. The method proved to be selective, precise, accurate and suitable for routine analysis for the determination of said compounds in 50-mg hair samples.


Assuntos
Ketamina , Espectrometria de Massas em Tandem , Espectrometria de Massas em Tandem/métodos , Cromatografia Gasosa-Espectrometria de Massas , Limite de Detecção , Reprodutibilidade dos Testes , Cabelo/química , Microextração em Fase Sólida/métodos
17.
Braz. j. med. biol. res ; 56: e12647, 2023. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1505885

RESUMO

DiGeorge syndrome is a disorder caused by a microdeletion on the long arm of chromosome 22. Approximately 1% of patients diagnosed with DiGeorge syndrome may have an absence of a functional thymus, which characterizes the complete form of the syndrome. These patients require urgent treatment to reconstitute T cell immunity. Thymus transplantation is a promising investigational procedure for reconstitution of thymic function in infants with congenital athymia. Here, we demonstrate a possible optimization of the preparation of thymus slices for transplantation through prior depletion of thymocytes and leukocyte cell lineages followed by cryopreservation with cryoprotective media (5% dextran FP 40, 5% Me2SO, and 5% FBS) while preserving tissue architecture. Thymus fragments were stored in liquid nitrogen at -196°C for 30 days or one year. The tissue architecture of the fragments was preserved, including the distinction between medullary thymic epithelial cells (TECs), cortical TECs, and Hassall bodies. Moreover, depleted thymus fragments cryopreserved for one year were recolonized by intrathymic injections of 3×106 thymocytes per mL, demonstrating the capability of these fragments to support T cell development. Thus, this technique opens up the possibility of freezing and storing large volumes of thymus tissue for immediate transplantation into patients with DiGeorge syndrome or atypical (Omenn-like) phenotype.

18.
Int J Pharm X ; 4: 100141, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36465275

RESUMO

The aim of this study was to better understand the long term behavior of silicone-based cochlear implants loaded with dexamethasone: in vitro as well as in vivo (gerbils). This type of local controlled drug delivery systems offers an interesting potential for the treatment of hearing loss. Because very long release periods are targeted (several years/decades), product optimization is highly challenging. Up to now, only little is known on the long term behavior of these systems, including their drug release patterns as well as potential swelling or shrinking upon exposure to aqueous media or living tissue. Different types of cylindrical, cochlear implants were prepared by injection molding, varying their dimensions (being suitable for use in humans or gerbils) and initial drug loading (0, 1 or 10%). Dexamethasone release was monitored in vitro upon exposure to artificial perilymph at 37 °C for >3 years. Optical microscopy, X-ray diffraction and Raman imaging were used to characterize the implants before and after exposure to the release medium in vitro, as well as after 2 years implantation in gerbils. Importantly, in all cases dexamethasone release was reliably controlled during the observation periods. Diffusional mass transport and limited drug solubility effects within the silicone matrices seem to play a major role. Initially, the dexamethasone is homogeneously distributed throughout the polymeric matrices in the form of tiny crystals. Upon exposure to aqueous media or living tissue, limited amounts of water penetrate into the implant, dissolve the drug, which subsequently diffuses out. Surface-near regions are depleted first, resulting in an increase in the apparent drug diffusivity with time. No evidence for noteworthy implant swelling or shrinkage was observed in vitro, nor in vivo. A simplified mathematical model can be used to facilitate drug product optimization, allowing the prediction of the resulting drug release rates during decades as a function of the implant's design.

19.
Mamm Genome ; 33(4): 619-628, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35816191

RESUMO

Cis-acting effects of noncoding variants on gene expression and regulatory molecules constitute a significant factor for phenotypic variation in complex traits. To provide new insights into the impacts of single-nucleotide polymorphisms (SNPs) on transcription factors (TFs) and transcription cofactors (TcoF) coding genes, we carried out a multi-omic analysis to identify cis-regulatory effects of SNPs on these genes' expression in muscle and describe their association with feed efficiency-related traits in Nelore cattle. As a result, we identified one SNP, the rs137256008C > T, predicted to impact the EEF1A1 gene expression (ß = 3.02; P-value = 3.51E-03) and the residual feed intake trait (ß = - 3.47; P-value = 0.02). This SNP was predicted to modify transcription factor sites and overlaps with several QTL for feed efficiency traits. In addition, co-expression network analyses showed that animals containing the T allele of the rs137256008 SNP may be triggering changes in the gene network. Therefore, our analyses reinforce and contribute to a better understanding of the biological mechanisms underlying gene expression control of feed efficiency traits in bovines. The cis-regulatory SNP can be used as biomarker for feed efficiency in Nelore cattle.


Assuntos
Ingestão de Alimentos , Locos de Características Quantitativas , Bovinos/genética , Animais , Ingestão de Alimentos/genética , Polimorfismo de Nucleotídeo Único , Fenótipo , Músculos , Expressão Gênica , Ração Animal
20.
Front Surg ; 9: 882625, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35813046

RESUMO

Anastomotic leakage is a major complication in gastrointestinal and colorectal surgery and its occurrence increases morbidity and mortality. Its incidence is even higher in Crohn's disease surgeries. Several authors have identified factors involved in the pathophysiology of anastomotic leak in the literature, aiming to reduce its occurrence and, therefore, improve its surgical treatment. Surgical technique is the most discussed topic in studies on guiding the performance of side-to-side stapled anastomosis. Preoperative nutritional therapy also has been shown to reduce the risk of anastomotic leakage. Other factors remain controversial - immunomodulator use and biologic therapy, antibiotics, and gut microbiota - with studies showing a reduction in the risk of complication while other studies show no correlation. Although mesenteric adipose tissue has been related to disease recurrence, there is no evidence in the literature that it is related to a higher risk of anastomotic leakage. Further exploration on this topic is necessary, including prospective research, to support the development of techniques to prevent anastomotic leakage, in this way benefiting the inflammatory bowel disease patients who have to undergo a surgical procedure.

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