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1.
Artigo em Inglês | MEDLINE | ID: mdl-38780841

RESUMO

Thermal pollution creates substantial challenges that alter energy demand and produce reactive oxygen species that damage fish DNA, proteins, and lipids. Rhamdia voulezi is a species of fish native to the Iguaçu river, Paraná, Brazil, that does not have scientific records of minimum (CTmin) and maximum (CTmax) temperatures required for survival. As it is a top predator species in the food chain and lives at temperatures below 22 °C, the loss of the species can cause functional problems in controlling the ecosystem and energy flow. The study evaluated the tissue metabolism of the brain, heart, and muscle of R. voulezi (n = 72) subjected to acute thermal stress of 31 °C for 2, 6, 12, 24, and 96 h after acclimatization to 21 °C. The biochemical markers SOD, GPx, MDH, HK, and CK of the brain, PCO of the heart and CAT, glycogen, G6PDH, and ALT of muscle were significant. PCA, IBR, thermal sensitive, and condition factor suggested that R. voulezi has different physiological strategies for acclimatization to 31 °C to mobilize and sustain the metabolic needs of oxygenation and energy allocation/utilization for tissue ATP production.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38688175

RESUMO

The present work aimed at the development and characterization of aroeira leaf flour (Schinus terebinthifolius Raddi), obtained by lyophilization and drying in an air circulation oven. The technological, physical, physico-chemical, morphological, functional, and microbiological aspects were analyzed. Physico-chemical analysis identified the following properties with values provided respectively for fresh leaves (FOin) and flours (FES and FLIO): low water activity (0.984, 0.370, 0.387 g/100 g), moisture (64.52, 5.37, 7.97 g /100 g), ash (2.69, 6.51, and 6.89 g/100 g), pH (0.89, 4.45, 4.48 g/100 g), lipids (0.84, 1.67, 5.23 g/100 g), protein (3.29, 8.23, 14.12 g/100 g), carbohydrates (17.02, 53.12, 33.02 g/100 g), ascorbic acid (19.70, 34.20, 36.90 mg/100 g). Sources of fiber from plant leaves and flours (11.64, 25.1, 32.89 g/100 g) showed increased levels of luminosity. For NMR, the presence of aliphatic and aromatic compounds with olefinic hydrogens and a derivative of gallic acid were detected. The most abundant minerals detected were potassium and calcium. Micrographs identified the presence of irregular, non-uniform, and sponge-like particles. The main sugars detected were: fructose, glucose, and maltose. Malic, succinic, citric, lactic, and formic acids were found. Fifteen phenolic compounds were identified in the samples, highlighting: kaempferol, catechin, and caffeic acid. The values ​​found for phenolics were (447, 716.66, 493.31 mg EAG/100 g), flavonoids (267.60, 267.60, 286.26 EC/100 g). Antioxidant activity was higher using the ABTS method rather than FRAP for analysis of FOin, FES, and FLIO. Since the flours of the aroeira leaf have an abundant matrix of nutrients with bioactive properties and antioxidant activity, they have a potential for technological and functional use when added to food.


Assuntos
Anacardiaceae , Farinha , Folhas de Planta , Folhas de Planta/química , Anacardiaceae/química , Farinha/análise , Liofilização , Carboidratos/análise , Carboidratos/química , Antioxidantes/análise , Antioxidantes/química , Schinus
3.
J Reconstr Microsurg ; 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38657631

RESUMO

BACKGROUND: Studies have shown a significant reduction in breast cancer-related lymphedema (BCRL) rates in patients undergoing complete axillary lymph node dissection (cALND) combined with immediate lymphatic reconstruction (ILR) using lymphovenous bypass (LVB).The purpose of this study was to determine if ILR with LVB at the time of cALND results in a decreased incidence of BCRL and its impact on patient quality of life (QOL). METHODS: In this prospective cohort study, patients ≥ 18 years requiring cALND underwent ILR from 2019 to 2021. The primary outcome was bilateral upper limb volumes measured by Brørson's truncated cone formula and the Pero-System (3D Körper Scanner). The secondary outcome was QOL measured by the Lymphedema Quality of Life (LYMQOL) arm patient-reported outcome measurement. RESULTS: Forty-two patients consented to ILR using LVB. ILR was completed in 41 patients with a mean of 1.9 ± 0.9 lymphovenous anastomosis performed. Mean age of patients was 52.4 ± 10.5 years with a mean body mass index of 27.5 ± 4.9 kg/m2. All patients (n = 39, 100%) received adjuvant therapy after ILR. Mean follow-up was 15.2 ± 5.1 months. Five patients met criteria for lymphedema throughout the duration of the study (12.8%), with two patients having resolution, with an overall incidence of 7.7% by the end of the study period. Patients with lymphedema were found to have statistically significant lower total LYMQOL values at 18 months (8.44 ± 1.17 vs. 3.23 ± 0.56, p < 0.001). A mean increase of 0.73 ± 3.5 points was observed for overall QOL average for upper limb function at 18 months compared with 3 months (t = 0.823, p = 0.425). CONCLUSION: This study showed an incidence of 7.7% lymphedema development throughout the duration of study. We also showed that ILR has the potential to reduce the significant long-term adverse outcomes of lymphedema and improve QOL for patients undergoing cALND.

4.
Ecol Evol ; 14(2): e10864, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38304267

RESUMO

Multibiomarker studies are useful to evaluate the early warning signs of environmental degradation, and their unified responses are often assessed through two common indexes, Integrated Biomarker Response (IBR) and Integrated Biological Responses version 2 (IBRv2). The R package IBRtools allows users to calculate both IBR and IBRv2 while simultaneously incorporating all the biomarkers under evaluation. The package includes functions for calculating the indexes IBR and IBRv2 and obtaining their standardized values, as well a function for radar chart creation and three example datasets. Here we describe the main algorithms involved in IBR and IBRv2 calculations, a description of the novel package and illustrate a workflow using data examples available on the package to guide the user on how to accurately acquire the values for either the IBR index or the IBRv2 index. The IBRtools package provides a user-friendly platform for R users to obtain IBR index and IBRv2 values, making it straightforward even for large datasets.

5.
J Aquat Anim Health ; 36(1): 16-31, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38217492

RESUMO

OBJECTIVE: Ectothermic fish are directly affected by temperature changes in the environment. The aim of this study was to evaluate the metabolic responses in the gills of Yellowtail Lambari Astyanax lacustris under thermal stress. METHODS: To this end, we used spectrophotometry to evaluate the biomarkers of carbohydrate and protein metabolism, antioxidant defense, and oxidative damage in fish subjected to low (15°C) and high (31°C) temperatures, with control groups held at 23°C, for 2, 6, 12, 24, 48, and 96 h. RESULT: The results showed that cold thermal stress did not change the energy demand, and the antioxidant defense was reduced; therefore, the gills were vulnerable to the action of reactive oxygen species (ROS), presenting increased protein carbonylation at 12 h. With heat thermal stress, a higher energy demand was observed, which was verified by an increase in aerobic metabolism by glycolysis and the citric acid cycle. High-temperature stress also increased the antioxidant defenses, as verified by the increased activities of glutathione peroxidase, glutathione reductase, and glutathione S-transferase. However, the antioxidant defense system could not protect tissues from the action of ROS, as protein carbonylation increased at 6 and 24 h, indicating oxidative stress. CONCLUSION: The results showed that (1) temperature variations caused metabolic adjustments in the gills of Yellowtail Lambari, (2) the adaptive responses were different for winter and summer temperatures, and (3) Yellowtail Lambari recovered homeostasis when subjected to thermal stress, even with the occurrence of oxidative stress.


Assuntos
Antioxidantes , Perciformes , Animais , Antioxidantes/metabolismo , Temperatura , Espécies Reativas de Oxigênio/metabolismo , Catalase/metabolismo , Brânquias , Superóxido Dismutase/metabolismo , Estresse Oxidativo/fisiologia , Peixes/metabolismo , Glutationa Transferase/metabolismo
6.
Fish Physiol Biochem ; 50(2): 617-633, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38175338

RESUMO

Exposure to high temperatures induces changes in fish respiration, resulting in an increased production of reactive oxygen species. This, in turn, affects the enzymatic and non-enzymatic components of antioxidant defenses, which are essential for mitigating cellular stress. Rhamdia voulezi, an economically important fish species endemic to Brazil's Iguaçu River, served as the subject of our study. Our goal was to assess enzymatic antioxidant biomarkers (superoxide dismutase, catalase, glutathione peroxidase, glutathione S-transferase, glutathione reductase, glucose-6-phosphate dehydrogenase), non-protein thiol levels (reduced glutathione), and markers of oxidative damage (lipoperoxidation and carbonylation) in the liver, gills, and kidneys of R. voulezi after acute exposure to high temperatures (31°C) for 2, 6, 12, 24, and 96 h. Control groups were maintained at 21°C. Our findings revealed that the liver exhibited increased superoxide dismutase levels up to 12 h and elevated glutathione S-transferase levels at 12 and 96 h at 31°C. In the gills, superoxide dismutase levels increased up to 24 h, along with increased lipoperoxidation at 2, 6, 12, and 96 h of exposure to high temperatures. The kidneys responded to heat stress at 12 h, with an increase in superoxide dismutase and catalase activity, and lipid peroxidation was observed at 2 and 6 h at 31°C. The three tissues evaluated responded differently to heat stress, with the liver demonstrating greater physiological adjustment to high temperatures. The intricate interplay of various antioxidant defense biomarkers and oxidative damage suggests the presence of oxidative stress in R. voulezi when exposed to high temperatures.


Assuntos
Antioxidantes , Peixes-Gato , Animais , Antioxidantes/metabolismo , Catalase/metabolismo , Temperatura , Estresse Oxidativo/fisiologia , Glutationa/metabolismo , Peixes-Gato/metabolismo , Superóxido Dismutase/metabolismo , Biomarcadores/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Transferase/metabolismo , Brânquias/metabolismo , Peroxidação de Lipídeos
7.
Mem Inst Oswaldo Cruz ; 118: e230071, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37729273

RESUMO

BACKGROUND: Leishmania RNA virus 1 (LRV1) is commonly found in South American Leishmania parasites belonging to the subgenus Viannia, whereas Leishmania RNA virus 2 (LRV2) was previously thought to be restricted to the Old-World pathogens of the subgenus Leishmania. OBJECTIVES: In this study, we investigated the presence of LRV2 in strains of Leishmania (L.) infantum, the causative agent of visceral leishmaniasis (VL), originating from different hosts, clinical forms, and geographical regions. METHODS: A total of seventy-one isolates were screened for LRV2 using semi-nested reverse transcription-polymerase chain reaction (RT-PCR) targeting the RNA-dependent RNA polymerase (RdRp) gene. FINDINGS: We detected LRV2 in two L. infantum isolates (CUR268 and HP-EMO) from canine and human cases, respectively. MAIN CONCLUSIONS: To the best of our knowledge, this is the first detection of LRV2 in the New World.


Assuntos
Leishmania infantum , Leishmaniose Visceral , Humanos , Animais , Cães , Leishmania infantum/genética , Leishmaniose Visceral/veterinária , Brasil , RNA Polimerase Dependente de RNA
8.
J Psychiatr Res ; 164: 98-117, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37331263

RESUMO

The objective was to evaluate the effects of the consumption of a mix of baru almond and goat whey on memory performance and anxiety parameters related to the intestinal health of rats treated during aging. The animals were divided into three groups and treated by gavage for 10 weeks (n = 10/each group): Control (CT) - distilled water; Baru almond (BA) - 2000 mg of baru/kg of body weight; and Baru + Whey (BW) - 2000 mg of baru + 2000 mg of goat milk whey/kg of body weight. Anxiety behavior, memory, brain fatty acid profile and fecal microbiota were measured. BA and BW realized less grooming, spent more time in the central area of the open field and the open arms, and realized more head dipping in the elevated plus maze. A higher rate of exploration of the new object in the short and long-term memory was observed in BA and BW. There was an increase in the deposition of MUFAs and PUFAs and oleic acid in the brain of BA and BW. Regarding spatial memory, BA and BW performed better, with an emphasis on BW. There was a beneficial modulation of the fecal microbiota with a reduction of the pathogenic genus Clostridia_UFC-014 in BA and BW and an increase in the abundance of metabolic pathways of interest in the brain-gut axis. Thus, consumption of the mix is efficient in beneficially altering the intestinal microbiota, improving memory and anxiolytic-like behavior in rats during aging.


Assuntos
Ansiolíticos , Dipteryx , Microbioma Gastrointestinal , Prunus dulcis , Ratos , Animais , Soro do Leite , Cabras , Peso Corporal
9.
Mol Cell Biochem ; 478(11): 2445-2450, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36790551

RESUMO

Leishmaniasis is a zoonotic disease with worldwide distribution. In the Americas, the causative agent of the visceral form is the protozoa Leishmania (Leishmania) infantum. Transmission to the host or vertebrate reservoir occurs through the bite of infected arthropod females like Lutzomyia longipalpis. The epidemiological connection between the infection in dogs and humans generate constant studies about the relationship between the parasite and the canine host, including the development of methods and tests for the detection and quantification ofLeishmania (L.) infantum. Both conventional PCR (cPCR) and quantitative PCR (qPCR) can be used in the diagnosis of the parasite. Dropet Digital PCR (ddPCR) is another useful tool. Knowing the parasite load and its relationship with the clinical signs of naturally infected dogs is useful in research development and for establishing treatments that reduce the transmission of the disease. In this study, thirty-nine clinical samples of spleen from dogs naturaly infected by L. infantum were collected after necropsy. Two molecular tools were used to quantify the parasite load (qPCR and ddPCR) and there was 100% agreement in the results of the them. The tools developed in this work are important for the detection of L. infantum in dogs and humans. Droplet Digital PCR does not require a standard curve and is easy to standardize. In such manner, this new tool can generate more in-depth information in the broad debate about parasitic loads and the pathogenesis of leishmaniasis.

10.
Rev. Pesqui. Fisioter ; 13(1)fev., 2023. tab
Artigo em Inglês, Português | LILACS | ID: biblio-1451245

RESUMO

INTRODUÇÃO: Segundo a Organização Mundial da Saúde, a síndrome de Burnout (SB) é uma resposta à cronificação do estresse, estrita ao contexto laboral. Alguns estudos reconheceram essa condição em 1980 e destacaram a exaustão emocional, a despersonalização e um senso reduzido de realização pessoal experimentados pelos profissionais. Existe uma necessidade de entender a síndrome de Burnout nos fisioterapeutas, e o agravamento que a pandemia da COVID-19 provocou nestes profissionais atuantes nas áreas da docência, em clínicas e área hospitalar. OBJETIVO: Verificar a frequência da síndrome de Burnout em fisioterapeutas e associar o impacto do ambiente de trabalho e em cada área de atuação no período da pandemia da COVID-19. METODOLOGIA: Trata-se de um estudo observacional, descritivoanalítico, de abordagem quantitativa e delineamento transversal. Como instrumentos de avaliação foram utilizados questionários de coleta de dados sociodemográficos, ocupacionais e comportamentais, além do Maslach Burnout Inventory (MBI) em sua versão Human Services Survey (HSS). Os critérios de inclusão consistiam em idade (22 a 70 anos), ambos os gêneros, devidamente habilitados pelo conselho da profissão, que atuassem em pelo menos um local fixo de atendimento por um período mínimo de 06 meses. A análise dos dados foi feita através do teste T, Anova, Kruskal ­ Wallis e Mann ­ Whitney. O nível de significância foi definido em p<0,05 e ICs de 95%. RESULTADOS: Participaram 57 profissionais fisioterapeutas atuantes em clínicas, hospitais e professores. Comparamos os 03 critérios da SB e o seu score total e correlacionamos aos 03 cenários, neste quesito os três grupos Síndrome de Burnout, pois a literatura preconiza que alta exaustão emocional, associada a alta despersonalização e baixa realização pessoal é considerada uma síndrome de Burnout. CONCLUSÃO: Os fisioterapeutas apresentam alto nível de incidência da SB, foi constatado que a pandemia agravou a prevalência e o impacto da SB nos profissionais que atuam em hospitais, clínicas e na docência.


INTRODUCTION: According to the World Health Organization, Burnout syndrome is a response to the chronification of stress, strict to the work context. Some studies recognized this condition in 1980 and highlighted emotional exhaustion, depersonalization and a reduced sense of personal accomplishment experienced by professionals. There is a need to understand the Burnout syndrome in physical therapists, and the aggravation of the COVID-19 pandemic in these professionals working in the teaching, clinical and hospital áreas. OBJECTIVE: To verify the frequency of Burnout syndrome in physical therapists and to associate the impact of the work environment and the work variables in each area of work in the period of the COVID-19 pandemic. METHODOLOGY: This is an observational, descriptiveanalytical study with a quantitative approach and cross-sectional design. A questionnaire was used to collect sociodemographic, occupational and behavioral data, as well as the Maslach Burnout Inventory (MBI) in its Human Services Survey (HSS) version. The inclusion criteria were age (22 to 70 years old), both genders, duly qualified by the professional council, and working in at least one fixed place of attendance for a minimum period of 06 months. Data analysis was done using the T test, Anova, Kruskal-Wallis and Mann-Whitney. The significance level was set at p<0.05 and 95% CIs. RESULTS: 57 physiotherapist professionals working in clinics, hospitals and teaching participated. We compared the 03 criteria of the BS and its total score and correlated the 03 scenarios, in this regard, the three groups had Burnout Syndrome, since the literature recommends that high emotional exhaustion, associated with high depersonalization and low personal fulfillment is considered a syndrome of Burnout. CONCLUSION: Physical therapists have a high level of incidence of BS, it was found that the pandemic aggravated the prevalence and impact of BS on professionals working in hospitals, clinics and teaching.


Assuntos
Esgotamento Profissional , Estresse Ocupacional , COVID-19
11.
Biochimie ; 210: 3-13, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36273764

RESUMO

Temperature is an important factor that conditions the physiological responses of fish, generating a stressful condition when in non-ideal parameters. Thus, the objective was to evaluate metabolic aspects in the muscle of fish Astyanax lacustris submitted to thermal shock. The specimens were subjected to 2, 6, 12, 24, 48, and 96 h of exposure to 15 °C and 31 1 °C, with their respective controls 23 °C. At 15 °C there was a reduction in glycogenolysis in the initial periods indicated by changes in glycogen phosphorylase (GP), pyruvate and lactate. Subsequently, there was an increase in GP activity, pyruvate levels and hexokinase activity in the next time periods, suggesting an increase in energy demand. At 31 °C there was observed low need for the protein metabolism, indicated by reduction in the activity of aspartate aminotransferase and alanine aminotransferase. At 15 °C, initial periods show an increase in glutathione reductase activity and an increase in carbonylated protein levels, indicating induction of oxidative stress for muscle. At 31 °C, there was a punctual increase in reduced glutathione levels at 24 h. In addition, the integrated biomarker response index proved to be a good ally in the evaluation of a set of biomarkers, corroborating the results observed by the biomarkers individually. Thus, it is possible to conclude that the acute thermal shock affects the metabolism of A. lacustris muscle, which undergoes rearrangements to deal with temperature, where 15 °C is more stressful than 31 °C.


Assuntos
Antioxidantes , Músculos , Animais , Músculos/metabolismo , Antioxidantes/metabolismo , Estresse Oxidativo , Metabolismo dos Carboidratos , Biomarcadores/metabolismo
12.
Plast Reconstr Surg ; 151(4): 552e-562e, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36461897

RESUMO

BACKGROUND: There has been a recent increase in the number and complexity of quality improvement (QI) studies in breast reconstruction. To assist with the development of thorough QI reporting practices, with the goal of improving the transferability of these initiatives, the authors conducted a systematic review of studies describing the implementation of QI initiatives in breast reconstruction. The authors used the Standards for Quality Improvement Reporting Excellence (SQUIRE) 2.0 guideline to appraise the quality of reporting of these initiatives. METHODS: English language articles published in Embase, MEDLINE, CINAHL, and the Cochrane databases were searched. Quantitative studies evaluating the implementation of QI initiatives in breast reconstruction were included. The primary endpoint of interest in this review was the distribution of studies according to SQUIRE 2.0 criteria scores in proportions. Abstracts and full-text screening, and data extraction were completed independently and in duplicate by the review team. RESULTS: The authors screened 1107 studies, of which 53 full texts were assessed and 35 met inclusion criteria. In our assessment, only three studies (9%) met all 18 SQUIRE 2.0 criteria. SQUIRE 2.0 criteria that were met most frequently were abstract, problem description, rationale, and analysis. The lowest SQUIRE 2.0 scores appeared in the interpretation criteria. CONCLUSIONS: Significant opportunity exists to improve QI reporting in breast reconstruction, especially in the realm of costs, strategic tradeoffs, ethical considerations, project sustainability, and potential for spread to other contexts. Improvements in these areas will help to further advance the transferability of QI initiatives in breast reconstruction.


Assuntos
Mamoplastia , Melhoria de Qualidade , Humanos , Mamoplastia/normas
13.
Mem. Inst. Oswaldo Cruz ; 118: e230071, 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1514607

RESUMO

BACKGROUND Leishmania RNA virus 1 (LRV1) is commonly found in South American Leishmania parasites belonging to the subgenus Viannia, whereas Leishmania RNA virus 2 (LRV2) was previously thought to be restricted to the Old-World pathogens of the subgenus Leishmania. OBJECTIVES In this study, we investigated the presence of LRV2 in strains of Leishmania (L.) infantum, the causative agent of visceral leishmaniasis (VL), originating from different hosts, clinical forms, and geographical regions. METHODS A total of seventy-one isolates were screened for LRV2 using semi-nested reverse transcription-polymerase chain reaction (RT-PCR) targeting the RNA-dependent RNA polymerase (RdRp) gene. FINDINGS We detected LRV2 in two L. infantum isolates (CUR268 and HP-EMO) from canine and human cases, respectively. MAIN CONCLUSIONS To the best of our knowledge, this is the first detection of LRV2 in the New World.

14.
Brain Res ; 1797: 148118, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36240883

RESUMO

Change in temperature of aquatic environment have impacts on the physiology of fish, especially in the brain, which is a vital organ and prone to oxidative damage. Astyanax lacustris is a freshwater fish that play an important role in the food market and has been increasingly used in fish farms, besides environmental monitoring studies. Therefore, this study aimed to evaluate the responses of antioxidant biomarkers and products of the oxidative process in the brains A. lacustris subjected to thermal shock. The specimens were obtained from artificial farming lakes and subjected to shock induced by exposure to high (31 °C ± 0.5) and low (15 °C ± 0.5) temperature for 2, 6, 12, 24, 48, 72 and 96 h; control group were maintained at 23 °C ± 0.5. At 31 °C, glutathione-related enzymes were more responsive, suggested by the change activity of GPx and G6PDH enzymes, in addition to GSH levels. At 15 °C, enzymes of the first line of defense were more active, evidenced by the change CAT activity. No significant changes were detected in the levels of ROS, LPO and PCO. These results indicate that the brains of A. lacustris have an efficient antioxidant defense system with the ability to acclimatize to the temperatures tested.

15.
Food Chem ; 397: 133784, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-35917782

RESUMO

Bioactive peptides derived from food proteins have important biological effects. The search for new bioactive peptides from natural sources needs to base their decisions on evidence from methods providing structural information, where classic biological assays do not provide it. In this context, high-performance thin-layer chromatography (HPTLC) coupled with bioassays in effect-directed analysis (EDA) has been used recently to detect the bioactivities of peptides. In EDA, peptides are separated and the biological effects of individual fractions can be determined. HPTLC-EDA coupled with MS represents an emerging technology, complementary to the more common HPLC and electrophoresis analytical methods used for peptide analysis. In addition, thin-layer chromatography (TLC) can be used to identify the origins of substances causing biological effects. This review provides an overview of the status of analytical methods in these systems as well as new strategies for the detection and characterization of bioactive peptides.


Assuntos
Bioensaio , Peptídeos , Bioensaio/métodos , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina/métodos , Extratos Vegetais/química
16.
J Fish Biol ; 100(5): 1245-1263, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35266159

RESUMO

Predictions about global warming have raised interest in assessing whether ectothermic organisms will be able to adapt to these changes. Understanding the physiological mechanisms and metabolic adjustment capacity of fish subjected to heat stress can provide subsidies that may contribute to decision-making in relation to ecosystems and organisms subjected to global climate change. This study investigated the antioxidant defence system and energy metabolism of carbohydrate and protein responses in the gill, liver and kidney tissues of Psalidodon bifasciatus (Garavello & Sampaio 2010), a Brazilian freshwater fish used in aquaculture and in biological studies, following exposure to heat shock at 31°C for 2, 6, 12, 24 and 48 h. The fish presented signs of stress in all tissues tested, as evidenced by increased lipid peroxidation concentration at 2 h and phosphofructokinase, hexokinase and malate dehydrogenase activity at 48 h in the gills; increased glutathione-S-transferase activity at 12 h, citrate synthase activity at 24 h and concentration of reduced glutathione (GSH) concentration at 12 and 48 h in the liver; and through increased activity of superoxide dismutase at 48 h, glutathione reductase at 24 h, glucose-6-phosphate dehydrogenase at 48 h and concentration of GSH at 24 h in the kidney. In the kidneys, changes in the antioxidant system were more prominent, whereas in the gills, there were greater changes in the carbohydrate metabolism. These results indicated the importance of glycolysis and aerobic metabolism in the gills, aerobic metabolism in the liver and pentose-phosphate pathway in the kidneys during homeostasis. The biomarker response was tissue specific, with the greatest number of biomarkers altered in the gills, followed by those in the kidneys and liver.


Assuntos
Antioxidantes , Characidae , Animais , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Characidae/metabolismo , Ecossistema , Metabolismo Energético , Brânquias/metabolismo , Glutationa/metabolismo , Glutationa/farmacologia , Glutationa Peroxidase/metabolismo , Glutationa Peroxidase/farmacologia , Resposta ao Choque Térmico , Peroxidação de Lipídeos , Fígado/metabolismo , Estresse Oxidativo , Superóxido Dismutase/metabolismo , Superóxido Dismutase/farmacologia
17.
J Comp Physiol B ; 192(1): 77-94, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34591144

RESUMO

Subtropical fish are exposed to seasonal variations in temperature that impose a set of adaptations on their metabolism necessary for the maintenance of homeostasis. In this study, we addressed the effects of temperature variation on the metabolism of Astyanax lacustris, a species of freshwater fish common in the subtropical region of Brazil. Biomarkers of carbohydrate and protein metabolism, antioxidant defense, and oxidative damage were evaluated in the liver of A. lacustris exposed to low (15 °C) and high (31 °C) temperature thermal shock, with controls at 23 °C for 2, 6, 12, 24, 48, 72, and 96 h. A high energy demand was observed during the first 48 h of exposure to 15 °C, which is necessary for metabolic adjustment at low temperatures, with an increase in glycolysis, citric acid cycle, and amino acid catabolism. In addition, at 31 °C, glucose was exported in the first 12 h of exposure, and an increase in the citric acid cycle suggested acetyl-CoA as the pathway substrate, originating from the oxidation of lipids. The antioxidant defenses did not change at 15 °C, as opposed to 31 °C, in which there were changes in several antioxidant defense markers, indicating a response to the production of ROS. However, oxidative stress was observed at both temperatures, with oxidative damage detected by lipid peroxidation at 15 °C and protein carbonylation at 31 °C.


Assuntos
Characidae , Caraciformes , Animais , Antioxidantes/metabolismo , Characidae/metabolismo , Caraciformes/metabolismo , Metabolismo Energético , Água Doce
18.
Front Pharmacol, v. 12, 812295, jan. 2022
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-4137

RESUMO

Varespladib (VPL) was primarily developed to treat inflammatory disturbances associated with high levels of serum phospholipase A2 (PLA2). VPL has also demonstrated to be a potential antivenom support agent to prevent PLA2-dependent effects produced by snake venoms. In this study, we examined the action of VPL on the coagulant, haemorrhagic and enzymatic activities of Lachesis muta rhombeata (South-American bushmaster) venom. Conventional colorimetric enzymatic assays were performed for PLA2, caseinolytic and esterasic activities; in vitro coagulant activities for prothrombin time (PT) and activated partial thromboplastin time (aPTT) were performed in rat citrated plasma through a quick timer coagulometer, whereas the dimensions of haemorrhagic haloes obtained after i.d. injections of venom in Wistar rats were determined using ImageJ software. Venom (1 mg/ml) exhibited accentuated enzymatic activities for proteases and PLA2 in vitro, with VPL abolishing the PLA2 activity from 0.01 mM; VPL did not affect caseinolytic and esterasic activities at any tested concentrations (0.001–1 mM). In rat citrated plasma in vitro, VPL (1 mM) alone efficiently prevented the venom (1 mg/ml)-induced procoagulant disorder associated to extrinsic (PT) pathway, whereas its association with a commercial antivenom successfully prevented changes in both intrinsic (aPTT) and extrinsic (PT) pathways; commercial antivenom by itself failed to avoid the procoagulant disorders by this venom. Venom (0.5 mg/kg)-induced hemorrhagic activity was slightly reduced by VPL (1 mM) alone or combined with antivenom (antivenom:venom ratio 1:3 ‘v/w’) in rats, with antivenom alone producing no protective action on this parameter. In conclusion, VPL does not inhibit other major enzymatic groups of L. m. rhombeata venom, with its high PLA2 antagonize activity efficaciously preventing the venom-induced coagulation disturbances.

19.
Artigo em Inglês | MEDLINE | ID: mdl-34254899

RESUMO

High-performance thin-layer chromatography (HPTLC) and HPTLC coupled with mass spectrometry (MS) methods were described for the simultaneous determination of zearalenone (ZEA); type B trichothecenes (TCT-B); nivalenol (NIV) and deoxynivalenol (DON) along with its acetylated derivatives: 3-acetyldeoxynivalenol (3-ADON) and 15-acetyldeoxynivalenol (15-ADON). The extract samples were cleaned-up with Bond Elut Mycotoxin® solid-phase extraction cartridges. Then, separation was performed on HPTLC silica gel 60 F254 plates using toluene, ethyl acetate and formic acid (1:8:1 v/v/v) as mobile phase. Derivatisation was then performed with 10% aluminium trichloride in 50% methanol. Mycotoxin standards and spiked cereals grains were identified by UV spots at 366 nm, with retention factors (RF) of 0.20 (NIV), 0.39 (DON), 0.45 (15-ADON), 0.50 (3-ADON) and 0.60 (ZEA). Some parameters of validation were determined. Calibration data (n = 5) fitted a linear regression model with determination coefficients, R2 > 0.99. The recovery was determined in triplicate at two levels, ranging from 84.3 ± 2.2% to 114.2 ± 11.7%. Detection limits ranged from 80 to 120 µg kg-1 and quantification limits ranged from 120.0 to 200 µg kg-1. The analysis by HPTLC/electrospray (ESI)-MS in negative mode confirmed the presence of TCT-B and ZEA standards in Chilean cereals with mass signals at m/z 355, 371, 337, and 317 for DON, NIV, 3-ADON and 15-ADON, and ZEA, respectively.


Assuntos
Cromatografia/métodos , Grão Comestível/química , Espectrometria de Massas/métodos , Tricotecenos do Tipo B/química , Zearalenona/química , Chile , Contaminação de Alimentos , Fusarium
20.
Sensors (Basel) ; 21(12)2021 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-34204348

RESUMO

The planning of safe paths is an important issue for autonomous robot systems. The Probabilistic Foam method (PFM) is a planner that guarantees safe paths bounded by a sequence of structures called bubbles that provides safe regions. This method performs the planning by covering the free configuration space with bubbles, an approach analogous to a breadth-first search. To improve the propagation process and keep the safety, we present three algorithms based on Probabilistic Foam: Goal-biased Probabilistic Foam (GBPF), Radius-biased Probabilistic Foam (RBPF), and Heuristic-guided Probabilistic Foam (HPF); the last two are proposed in this work. The variant GBPF is fast, HPF finds short paths, and RBPF finds high-clearance paths. Some simulations were performed using four different maps to analyze the behavior and performance of the methods. Besides, the safety was analyzed considering the new propagation strategies.


Assuntos
Robótica , Algoritmos , Simulação por Computador
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