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1.
An Acad Bras Cienc ; 96(2): e20231336, 2024.
Article in English | MEDLINE | ID: mdl-38747801

ABSTRACT

The disease coronavirus COVID-19 has been the cause of millions of deaths worldwide. Among the proteins of SARS-CoV-2, non-structural protein 12 (NSP12) plays a key role during COVID infection and is part of the RNA-dependent RNA polymerase complex. The monitoring of NSP12 polymorphisms is extremely important for the design of new antiviral drugs and monitoring of viral evolution. This study analyzed the NSP12 mutations detected in circulating SARS-CoV-2 during the years 2020 to 2022 in the population of the city of Manaus, Amazonas, Brazil. The most frequent mutations found were P323L and G671S. Reports in the literature indicate that these mutations are related to transmissibility efficiency, which may have contributed to the extremely high numbers of cases in this location. In addition, two mutations described here (E796D and R914K) are close and have RMSD that is similar to the mutations M794V and N911K, which have been described in the literature as influential on the performance of the NSP12 enzyme. These data demonstrate the need to monitor the emergence of new mutations in NSP12 in order to better understand their consequences for the treatments currently used and in the design of new drugs.


Subject(s)
COVID-19 , Mutation , SARS-CoV-2 , Viral Nonstructural Proteins , SARS-CoV-2/genetics , Brazil , Viral Nonstructural Proteins/genetics , COVID-19/virology , COVID-19/transmission , Mutation/genetics , Humans , Computer Simulation
2.
Braz J Biol ; 83: e274991, 2023.
Article in English | MEDLINE | ID: mdl-37909589

ABSTRACT

The objective of this study was to evaluate the water status, photosynthetic pigments, and photochemical efficiency of mini watermelon plants under salt stress and phosphate fertilization. The experiment was conducted in pots under greenhouse conditions in Pombal, PB, Brazil. The experimental design used was randomized blocks in a 5 × 4 factorial scheme, with five levels of electrical conductivity of irrigation water - ECw (0.3, 1.3, 2.3, 3.3, and 4.3 dS m-1) and four doses of phosphorus (60, 80, 100, and 120% of the recommendation), with three replicates. The relative water content in the tissues decreased with the increase in ECw levels in all phosphorus doses, with decreases of 7.05, 7.81 and 8.83% per unit increase in ECw, in plants fertilized with 80, 100 and 120% P2O5. On the other hand, ECw levels increased electrolyte leakage, regardless of phosphorus doses of the recommendation. The synthesis of photosynthetic pigments and the quantum efficiency of photosystem II were inhibited by increasing water salinity from 0.3 dS m-1 in plants grown under phosphorus doses above 60% of the recommendation. Water salinity from 0.3 dS m-1 reduced chlorophyll b contents, initial, maximum, and variable fluorescence of mini watermelon plants, with a decrease of 11.86, 4.51, 4.53, and 4.54% per unit increment of ECw, respectively.


Subject(s)
Citrullus , Phosphates , Photosynthesis , Saline Waters , Phosphorus
3.
Braz J Biol ; 83: e274595, 2023.
Article in English | MEDLINE | ID: mdl-37792747

ABSTRACT

The objective of this study was to evaluate the salicylic acid applications in attenuating the harmful effects of saline nutrient solution on the physiology and growth of 'Gaúcho' melon cultivated in the NFT hydroponic system. The experiment was conducted in a greenhouse, in Pombal-PB, Brazil. The cultivation system used was the Nutrient Film Technique - NFT hydroponics. A completely randomized split-plot design was used, with the plot referring to four levels of salinity in the nutrient solution - ECns (2.1 control, 3.2, 4.3, and 5.4 dS m-1) and the sub-plot four concentrations of salicylic acid (SA) (0, 1.5, 3.0, and 4.5 mM), applied via foliar spray, with six replications. Nutrient solution of 4.3 and 5.4 dS m-1 electrical conductivity promotes higher maximum and variable fluorescence, respectively. The stomatal conductance, transpiration, stem diameter, main branch length, leaf dry mass, and stem dry mass of 'Gaúcho' melon plants decrease with the increase in salinity of the nutrient solution. Salicylic acid increases the initial fluorescence and the main branch length of 'Gaúcho' melon plants in hydroponic cultivation. Salicylic acid at a concentration of 1.5 to 4.5 mM did not attenuate the effects of salt stress on the internal CO2 concentration, CO2 assimilation rate, and root dry mass of 'Gaúcho' melon plants.


Subject(s)
Carbon Dioxide , Cucurbitaceae , Hydroponics , Salicylic Acid/pharmacology , Fluorescence , Salt Stress , Chlorophyll
4.
Braz J Biol ; 83: e275322, 2023.
Article in English | MEDLINE | ID: mdl-37729213

ABSTRACT

Several studies have been conducted evaluating the management of fertilizers as strategies to mitigate the deleterious effects of salt stress, so the objective of this work was to evaluate the quality of 'Crioula' guava seedlings under irrigation with water of different salinity levels and fertilized with combinations of nitrogen and potassium. The experiment was performed in a protected (screened) environment using a randomized block design and analyzed in a 5 × 4 factorial scheme, with four replicates, with the plot formed by two plants. The treatments were formed from the combination of the factor electrical conductivity of irrigation water (ECw 0.3, 1.1, 1.9, 2.7 and 3.5 dS m-1), with the factor combinations (C) of nitrogen (N) and potassium (K2O) doses, being C1 = 70% N + 50% K2O, C2 = 100% N + 75% K2O, C3= 130% N + 100% K2O and C4= 160% N + 125% K2O. The recommended dose of 100% N and K, respectively, was 541.1 mg N dm-3 soil and 798.6 mg K dm-3 soil. The combinations of N and K fertilization corresponding to 70% N + 50% K2O and 100% N + 75% K2O of the recommended doses promoted greater growth of 'Crioula' guava seedlings. Water with ECw of 2.1 dS m-1 promotes the formation of quality 'Crioula' guava seedlings.


Subject(s)
Psidium , Seedlings , Salinity , Nitrogen , Potassium , Soil , Water
5.
Front Bioeng Biotechnol ; 11: 1227212, 2023.
Article in English | MEDLINE | ID: mdl-37588136

ABSTRACT

Introduction: Microbial systems, such as Escherichia coli, as host recombinant expression is the most versatile and the cheapest system for protein production, however, several obstacles still remain, such as recovery of soluble and functional proteins from inclusion bodies, elimination of lipopolysaccharides (LPS) contamination, incomplete synthesis, degradation by proteases, and the lack of post-translational modifications, which becomes even more complex when comes to membrane proteins, because they are difficult not only to produce but also to keep in solution in its active state. T-cell Immunoglobulin and Mucin domain 3 (TIM-3) is a type I transmembrane protein that is predominantly expressed on the surface of T lymphocytes, natural killer (NK) cells, dendritic cells, and macrophages, playing a role as a negative immune checkpoint receptor. TIM-3 comprises a single ectodomain for interaction with immune system soluble and cellular components, a transmembrane domain, and a cytoplasmic tail, responsible for the binding of signaling and scaffolding molecules. TIM-3 pathway holds potential as a therapeutic target for immunotherapy against tumors, autoimmunity, chronic virus infections, and various malignancies, however, many aspects of the biology of this receptor are still incompletely understood, especially regarding its ligands. Methods: Here we overcome, for the first time, the challenge of the production of active immune checkpoint protein recovered from bacterial cytoplasmic inclusion bodies, being able to obtain an active, and non-glycosylated TIM-3 ectodomain (TIM-3-ECD), which can be used as a tool to better understand the interactions and roles of this immune checkpoint. The TIM-3 refolding was obtained by the association of high pressure and alkaline pH. Results: The purified TIM-3-ECD showed the correct secondary structure and was recognized from anti-TIM-3 structural-dependent antibodies likewise commercial TIM-3-ECD was produced by a mammal cells system. Furthermore, immunofluorescence showed the ability of TIM-3-ECD to bind to the surface of lung cancer A549 cells and to provide an additional boost for the expression of the lymphocyte activation marker CD69 in anti-CD3/CD28 activated human PBMC. Discussion: Taken together these results validated a methodology able to obtain active checkpoint proteins from bacterial inclusion bodies, which will be helpful to further investigate the interactions of this and others not yet explored immune checkpoints.

6.
Braz J Biol ; 83: e273017, 2023.
Article in English | MEDLINE | ID: mdl-37255174

ABSTRACT

Considering the relevance of bell pepper and the limitations imposed by the deleterious effects of salt stress, especially in semi-arid regions, it is extremely important to establish strategies that can facilitate the use of saline water in vegetable production. In this scenario, this study aimed to evaluate the effect of the frequency of foliar application of salicylic acid on the morphophysiology and production of the bell pepper cv. "All Big" irrigated with saline water. The study was conducted at a greenhouse in Campina Grande - PB. The treatments were distributed in a completely randomized design and set up in a 4 × 4 factorial arrangement with three replications, corresponding to four application frequencies of salicylic acid (F1- No application of salicylic acid, F2 - Weekly application, F3- fortnightly application, and F4- monthly application) and four levels of electrical conductivity of irrigation water - ECw (0.8, 1.6, 2.4 and 3.2 dS m-1). The fortnightly application of salicylic acid at a concentration of 1.0 mM mitigated the effects of salt stress on the morphophysiology and production components of bell pepper cv. All Big cultivated with ECw of up to 2.4 dS m-1, which reinforces the hypothesis that salicylic acid can act as a signaling molecule and reduce the effects of saline stress in bell pepper, enabling the use of brackish water in agricultural activity, mainly in semi-arid regions of northeastern Brazil, which have a shortage of fresh water.


Subject(s)
Capsicum , Salicylic Acid , Salicylic Acid/pharmacology , Salt Stress , Agriculture , Vegetables
7.
Braz J Biol ; 83: e273404, 2023.
Article in English | MEDLINE | ID: mdl-37255204

ABSTRACT

The objective of this study was to evaluate the physiology and production of sugar-apple as a function of irrigation intervals and foliar application of proline under the conditions of Paraíba's semi-arid region. A randomized block design was laid out in a 4 × 2 factorial scheme, with treatments resulting from the combination of four irrigation intervals (1, 4, 8 and 12 days) and two concentrations of proline (0 and 10 mM), with four replicates, and the plot consisted of four usable plants. Increase in irrigation intervals reduced the gas exchange of sugar-apple plants at 298 days after transplanting. Exogenous application of proline at concentration of 10 mM increased contents of chlorophyll a, chlorophyll b, total chlorophyll and carotenoids and fruit fresh mass in plants grown under 12-day irrigation intervals.


Subject(s)
Dehydration , Malus , Chlorophyll A , Proline , Sugars
8.
Environ Monit Assess ; 195(6): 707, 2023 May 22.
Article in English | MEDLINE | ID: mdl-37212929

ABSTRACT

The exploration of unconventional hydrocarbons may be very effective in promoting economic development and confronting energy crisis around the world. However, the environmental risks associated with this practice might be an impediment if not adequately dimensioned. In this context, naturally occurring radioactive materials and ionizing radiation are sensitive aspects in the unconventional gas industry that may compromise the environmental sustainability of gas production and they should be properly monitored. This paper provides a radioecological assessment of the São Francisco Basin (Brazil) as part of an environmental baseline evaluation regarding the Brazilian potential for exploring its unconventional gas reserves. Eleven and thirteen samples of surface waters and groundwater were analyzed for gross alpha and beta using a gas flow proportional counter. A radiological background range was proposed using the ± 2 Median Absolute Deviation method. Using geoprocessing tools, the annual equivalent doses and lifetime cancer risk indexes were spatialized. Gross alpha and beta background thresholds in surface water ranged from 0.04-0.40 Bq L-1 to 0.17-0.46 Bq L-, respectively. Groundwater radiological background varies from 0.006-0.81 Bq L-1 to 0.06-0.72 Bq L-1 for gross alpha and beta, respectively. All environmental indexes are relatively higher in the south of the basin, probably a direct response to the local volcanic formations. Traçadal fault and local gas seepages might also influence the gross alpha and beta distribution. All samples have radiological indexes below the environmental thresholds, and should remain at acceptable levels with the development of the unconventional gas industry in Brazil.


Subject(s)
Groundwater , Natural Gas , Oil and Gas Fields , Environmental Monitoring , Risk Assessment , Radiation, Ionizing
9.
Braz J Biol ; 83: e270865, 2023.
Article in English | MEDLINE | ID: mdl-37222368

ABSTRACT

The present study aimed to evaluate concentrations and forms of application of salicylic acid used for water stress mitigation on the gas exchange and growth of yellow passion fruit. The experimental design was arranged in randomized blocks in a 4 × 4 × 2 factorial scheme, with four concentrations of salicylic acid (SA) via foliar application (0.0, 0.7, 1.4, and 2.1 mM), four SA concentrations via fertigation (0.0, 0.7, 1.4, and 2.1 mM), and two irrigation depths estimated based on the actual evapotranspiration - ETr (50 and 100% of ETr), with three replications. Water stress negatively affected the physiology and growth of yellow passion fruit seedlings at 75 days after sowing (DAS). The application of salicylic acid, regardless of the form of application, attenuates the effects of water stress on gas exchange and growth of yellow passion fruit, with the best results obtained when applying a concentration of 1.30 mM via leaf or 0.90 mM via fertirrigation. The combination of foliar application of AS and fertigation contributed to improve photosynthetic and growth parameters under water conditions of 50 and 100% of ETr. The foliar application of AS presents superior responses to the application via fertigation. These results reinforce the hypothesis that the attenuation of water stress by salicylic acid is related to the maintenance of gas exchange, which depends on the concentration and form of application, and studies testing combinations throughout the crop cycle become promising for advances in knowledge from the action of this phytohormone on abiotic stress.


Subject(s)
Passiflora , Dehydration , Fruit , Seedlings , Salicylic Acid
10.
Braz J Biol ; 83: e272615, 2023.
Article in English | MEDLINE | ID: mdl-37222374

ABSTRACT

The limitation in the quality of water sources for irrigation in the semi-arid region of northeastern Brazil is increasingly present, so it is necessary to use water with high concentrations of salts for agricultural production, which makes the use of elicitors essential to mitigate the harmful effects of salinity on plants. Given the above, the objective of this study was to evaluate the effects of foliar application of salicylic acid on the mineral composition and production of guava plants under salt stress conditions in the post-grafting phase. The experiment was carried out under greenhouse conditions, in a randomized block design, in a 2 × 4 factorial scheme, with two levels of electrical conductivity of irrigation water (0.6 and 3.2 dS m-1) and four concentrations of salicylic acid (0, 1.2, 2.4, and 3.6 mM), with three replicates. During the flowering stage of guava, N, P, and K contents accumulated in the leaves according to the following order of concentration: N > K > P. Foliar application of 1.2 mM of salicylic acid increases the leaf contents of N, P, and K in guava plants grown under irrigation with water of 0.6 dS m-1. Water salinity of 3.2 dS m-1 reduces the growth and production components of guava plants.


Subject(s)
Psidium , Salicylic Acid , Salt Stress , Minerals , Water
11.
Eur. j. prev. cardiol ; 30(Suppl 1): i377-i377, May 24, 2023.
Article in English | CONASS, Sec. Est. Saúde SP, SESSP-IDPCPROD, Sec. Est. Saúde SP | ID: biblio-1435902

ABSTRACT

INTRODUCTION: The 12-lead electrocardiogram (ECG-12) is a useful tool in the assessment of athletes. The prevalence of normal electrocardiographic findings in elite Brazilian football players (EBFP) of different ethnicities is not well described. PURPOSE: To compare the prevalence of normal ECG-12 findings in Caucasian, Mixed-race (MR), and Afro-Brazilian (AB) EBFP. METHODS: A multicenter cross-sectional descriptive study was conducted with exams performed on EBFP as a pre-participation assessment from February 18, 2002, through October 20, 2022. RESULTS: 4,363 EBFP from 51 professional clubs (from all five regions of Brazil; 15 states, and 21 cities), aged 15-35 years (median: 19 years; IQR: 16-23) were evaluated. 2,027 were Caucasians, 1,324 were MRs, and 1,012 were ABs. In general, we recorded 4,155 ECG-12 with normal variations (95.2%). Positive Sokolow-Lyon criteria for left ventricular hypertrophy was more prevalent in ABs (41.8%) than in Caucasians (33.4%), or MRs (32.7%). The prevalence of early repolarization in ABs (41.5%) was higher than in Caucasians (34.6%), or MRs (35.5%). The PR interval was longer in ABs (157.1 ms) than in Caucasians (151.4 ms), or MRs (153.3 ms), and the first-degree atrioventricular block was more frequent in ABs compared to MRs (4.2% vs. 2.3%, respectively). On the other hand, Caucasians had a higher prevalence of incomplete right bundle branch block (14.2%) than MRs (11.2%), or ABs (9.7%). In our sample, only three EBFP showed second-degree atrioventricular block Mobitz type I (0.07%; one Caucasian and two AB athletes). CONCLUSIONS: This is the first large study to compare the prevalence of ECG-12 findings in EBFP from different ethnic groups. Those of AB origin have a significantly higher prevalence of ECG-12 findings compatible with the athlete's heart than Caucasians and MRs.


Subject(s)
Brazil , Echocardiography , Ethnic Inequality , Soccer , Athletes
12.
Cryo Letters ; 44(6): 333-342, 2023.
Article in English | MEDLINE | ID: mdl-38311927

ABSTRACT

BACKGROUND: Tarenaya spinosa is a medicinal species used for treating respiratory and inflammatory diseases. Various biotechnological studies have been developed for in vitro establishment of plants and long-term conservation of this species. OBJECTIVE: This study aimed to establish a new cryopreservation protocol using the D cryo-plate technique for in vitro-grown shoot tips of T. spinosa. MATERIALS AND METHODS: Different steps of the cryopreservation procedure were evaluated in this work: preculture; sucrose concentration of calcium alginate gel; concentration and time of exposure to osmoprotective loading solution; time of exposure to silica gel; and regrowth on recovery medium. RESULTS: The optimal procedure included preculture with increasing sucrose concentration (from 0.25 to 0.50 M), encapsulation and dehydration over silica-gel for 60 min. Increasing sucrose concentration in the loading solution or exposure duration had a negative effect on recovery of cryopreserved shoot tips. However, the association of calcium alginate gel enriched with 0.6 M sucrose with post-rewarming culture with BAP for 2 weeks resulted in the most efficient cryopreservation protocol (76% survival and 70% shoot recovery). CONCLUSION: The plants developed after cryopreservation maintained their in vitro multiplication capacity and demonstrated the efficiency of long-term conservation by D cryo-plate technique for T. spinosa. Doi.org/10.54680/fr23610110512.


Subject(s)
Cryopreservation , Vitrification , Cryopreservation/methods , Cryoprotective Agents/pharmacology , Plant Shoots , Sucrose/pharmacology , Alginates/pharmacology
13.
Braz J Biol ; 82: e265069, 2022.
Article in English | MEDLINE | ID: mdl-36327399

ABSTRACT

Salt stress caused by excess salts present in irrigation water, is one of the biggest barriers in agricultural production, especially in semi-arid regions. Thus, the use of substances, such as salicylic acid, that minimize the deleterious effects of salinity on plants can be an alternative to ensure satisfactory production. In this context, the objective of this study was to evaluate the effects of different methods of application of salicylic acid on the growth, production and water use efficiency of cherry tomato plants under salt stress. The study was conducted in a greenhouse, using an Entisol soil with a sandy loam texture. The treatments were distributed in a completely randomized design, in a 2×4 factorial arrangement, corresponding to two levels of electrical conductivity of irrigation water - ECw (0.6 and 2.6 dS m-1) and four methods of application of salicylic acid (Control - without application of SA; via spraying; via irrigation and via spraying and irrigation), with five replicates and one plant per plot. The salicylic acid concentration used in the different methods was 1.0 mM. Application of salicylic acid via foliar spraying increased the growth, production and water use efficiency of cherry tomato plants. The salt stress induced by the electrical conductivity of 2.6 dS m-1 was attenuated by the foliar application of salicylic acid. The use of water of 2.6 dS m-1 associated with the application of salicylic acid via irrigation water further intensified the adverse effects of salinity on cherry tomato plants.


Subject(s)
Solanum lycopersicum , Salicylic Acid/pharmacology , Salinity , Salt Stress , Water
14.
Braz J Biol ; 82: e262664, 2022.
Article in English | MEDLINE | ID: mdl-36197402

ABSTRACT

The excess of salts present in the water can limit the hydroponic cultivation of melon in semi-arid regions of the Brazilian Northeast, making it necessary to use strategies that allow the use of these waters. Among these strategies, the use of elicitor substances stands out, such as salicylic acid. In this context, this study aimed to evaluate the effect of foliar application of salicylic acid in mitigating the harmful effects of salt stress on the morphophysiology and production of 'Gaúcho' melon cultivated in a hydroponic system. A completely randomized design was adopted in a split-plot scheme, with four levels of electrical conductivity of the nutrient solution - ECsn (2.1, 3.2, 4.3, and 5.4 dS m-1) considered the plots and four salicylic acid concentrations - SA (0, 1.5, 3.0, and 4.5 mM), the subplots, with six replications. The foliar application of salicylic acid concentrations did not mitigate the deleterious effects of salt stress on the morphophysiology and yield of melon grown in hydroponic system. The concentration of 4.5 mM of salicylic acid intensified the harmful effects of the salinity of the nutrient solution on gas exchange and fresh weight of hydroponic melon.


Subject(s)
Cucurbitaceae , Salicylic Acid , Hydroponics , Salicylic Acid/pharmacology , Salt Stress , Salts , Water
15.
Oper Dent ; 47(5): E222-E232, 2022 Sep 01.
Article in English | MEDLINE | ID: mdl-36121728

ABSTRACT

OBJECTIVE: To evaluate the influence of different protective barriers as a function of the photoactivation distances on the radiant exposure of several light-curing units (LCU). The influence of the protective barriers on the degree of conversion of an adhesive resin was also evaluated. METHODS: Five LCUs were evaluated: Valo Cordless-used in standard mode (Ultradent, South Jordan, USA); Radii-cal-used in continuous mode (SDI, Bayswater, AU); Emitter D-used in continuous mode (Schuster, Santa Maria, BR); Bluephase N-used in high-intensity mode (Ivoclar Vivadent, Schaan, LI); and Rainbow Curing Light-used in continuous mode (Axdent, Guangdong, CN). For each LCU, radiant exposure was measured with a spectrometer (MARC Resin Calibrator) using three different protective barriers (low-density polyethylene, polyvinyl chloride, or Radii-cal barrier sleeves) and five photoactivation distances (0, 2, 5, 10, and 20 mm). The degree of conversion of an adhesive resin (Adper Scotchbond Multi-Purpose, 3M ESPE, St. Paul, USA) was measured through Fourier-transform infrared spectroscopy. The translucency parameter of protective barriers was measured with a spectrophotometer. For all statistical tests, a significance level of α = 0.05 was set. RESULTS: For all LCUs tested, radiant exposure was found to be significantly influenced by both protective barriers and curing distance (p≤0.001). In general terms, all the protective barriers significantly decreased the radiant exposure. Radii-cal barrier sleeves were the protective barrier that most decreased the radiant exposure. Irrespective of the protective barrier used, none of the LCU equipment reached the required minimum radiant exposure of 16 J/cm2 at 10 mm of curing distance. The degree of conversion was not effected by either LCU or a protective barrier (p≥0.211). CONCLUSIONS: Protective barriers and photoactivation distance reduced the radiant exposure emitted by different LCUs.


Subject(s)
Curing Lights, Dental , Light-Curing of Dental Adhesives , Composite Resins/therapeutic use , Materials Testing , Polyethylene , Polyvinyl Chloride , Spectroscopy, Fourier Transform Infrared
16.
Braz J Biol ; 84: e261211, 2022.
Article in English | MEDLINE | ID: mdl-35792744

ABSTRACT

To mitigate the deleterious effects of salt stress, substances capable of acting as mitigators and/or inducers of tolerance to stress have been used, enabling the use of saline waters and contributing to the development of irrigated agriculture. In this context, the aim of the present study was to evaluate the effect of foliar spraying with hydrogen peroxide as an attenuator of salt stress effects on soursop morphophysiology. The experiment was conducted under greenhouse conditions in Campina Grande - PB, Brazil, using a randomized block design, in a 4 × 4 factorial arrangement, whose treatments resulted from the combination of four levels of electrical conductivity of irrigation water - ECw (0.8 - control, 1.6, 2.4, and 3.2 dS m-1) and four concentrations of hydrogen peroxide - H2O2 (0, 10, 20, and 30 µM), with three replicates. Foliar application of hydrogen peroxide at a concentration of 10 µM increased growth, chlorophyll synthesis, and relative water content in the leaves and consequently reduced the foliar water saturation deficit of soursop irrigated with ECw up to 1.6 dS m-1. The concentration of hydrogen peroxide of 30 µM intensified the salt stress on the electrolyte leakage in the leaf blade and the photosynthetic pigments of soursop, 270 days after transplanting.


Subject(s)
Annona , Hydrogen Peroxide , Hydrogen Peroxide/pharmacology , Photosynthesis , Plant Leaves/physiology , Salt Stress
17.
Braz J Med Biol Res ; 55: e11976, 2022.
Article in English | MEDLINE | ID: mdl-35857996

ABSTRACT

Non-biodegradable metals such as mercury accumulate in living organisms during life (bioaccumulation) and also within trophic webs (biomagnification) and may reach high concentrations in humans. The contamination of humans by mercury in drinking water and food may be common, in particular in riverside communities that have a diet rich in fish. In vitro studies of human cell lines exposed to the cytotoxic and mutagenic effects of methylmercury have shown that prolactin has potential cytoprotective properties and may act as a co-mitogenic factor and inhibitor of apoptosis. The present in vivo study investigated the protective potential of prolactin against the toxic effects of methylmercury in the mammal Mus musculus. Histological and biochemical analyses, together with biomarker of genotoxicity, were used to verify the protective potential of prolactin in mice exposed to methylmercury. The reduction in kidney and liver tissue damage was not significant. However, results of biochemical and genotoxic analyses were excellent. After prolactin treatment, a significant reduction was observed in biochemical parameters and mutagenic effects of methylmercury. The study results therefore indicated that prolactin has protective effects against the toxicity of methylmercury and allowed us to suggest the continuation of research to propose prolactin in the future, as an alternative to prevent the damage caused by mercury, especially in populations that are more exposed.


Subject(s)
Mercury , Methylmercury Compounds , Animals , DNA Damage , Fishes , Humans , Mammals/metabolism , Mercury/analysis , Mercury/metabolism , Mercury/toxicity , Methylmercury Compounds/toxicity , Mice , Prolactin/metabolism
18.
Braz J Med Biol Res ; 55: e11959, 2022.
Article in English | MEDLINE | ID: mdl-35766707

ABSTRACT

In early 2021, Brazil saw a dramatic recurrence in Covid-19 cases associated to the spread of a novel variant of the SARS-CoV-2 virus, the P1 variant. In light of previous reports showing that this variant is more transmissible and more likely to infect people who had recovered from previous infection, a retrospective analysis was conducted to assess if the early 2021 Covid-19 wave in Brazil was associated with an increase in the number of individuals presenting with a more severe clinical course. Fifty-one thousand and fourteen individuals who underwent telemedicine consultations were divided into two groups: patients seen on or before January 31, 2021, and on or after February 1, 2021. These dates were chosen based on the spread of the P1 variant in Brazil. Referral to the emergency department (ED) was used as a marker of a more severe course of the disease. No differences were seen in the proportion of patients referred to the ED in each group nor in the odds ratio of being referred to the ED from the 1st of February 2021 (OR=0.909; 95%CI: 0.81-1.01). Considering the entire cohort, age had an impact on the odds of being referred to the ED, with individuals older than 59 years showing twice the risk of the remaining population and those less than 19 years showing a lower risk.


Subject(s)
COVID-19 , Telemedicine , Brazil/epidemiology , Humans , Middle Aged , Retrospective Studies , SARS-CoV-2
19.
Braz. j. med. biol. res ; 55: e11959, 2022. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1384150

ABSTRACT

In early 2021, Brazil saw a dramatic recurrence in Covid-19 cases associated to the spread of a novel variant of the SARS-CoV-2 virus, the P1 variant. In light of previous reports showing that this variant is more transmissible and more likely to infect people who had recovered from previous infection, a retrospective analysis was conducted to assess if the early 2021 Covid-19 wave in Brazil was associated with an increase in the number of individuals presenting with a more severe clinical course. Fifty-one thousand and fourteen individuals who underwent telemedicine consultations were divided into two groups: patients seen on or before January 31, 2021, and on or after February 1, 2021. These dates were chosen based on the spread of the P1 variant in Brazil. Referral to the emergency department (ED) was used as a marker of a more severe course of the disease. No differences were seen in the proportion of patients referred to the ED in each group nor in the odds ratio of being referred to the ED from the 1st of February 2021 (OR=0.909; 95%CI: 0.81-1.01). Considering the entire cohort, age had an impact on the odds of being referred to the ED, with individuals older than 59 years showing twice the risk of the remaining population and those less than 19 years showing a lower risk.

20.
Braz. j. med. biol. res ; 55: e11976, 2022. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1384153

ABSTRACT

Non-biodegradable metals such as mercury accumulate in living organisms during life (bioaccumulation) and also within trophic webs (biomagnification) and may reach high concentrations in humans. The contamination of humans by mercury in drinking water and food may be common, in particular in riverside communities that have a diet rich in fish. In vitro studies of human cell lines exposed to the cytotoxic and mutagenic effects of methylmercury have shown that prolactin has potential cytoprotective properties and may act as a co-mitogenic factor and inhibitor of apoptosis. The present in vivo study investigated the protective potential of prolactin against the toxic effects of methylmercury in the mammal Mus musculus. Histological and biochemical analyses, together with biomarker of genotoxicity, were used to verify the protective potential of prolactin in mice exposed to methylmercury. The reduction in kidney and liver tissue damage was not significant. However, results of biochemical and genotoxic analyses were excellent. After prolactin treatment, a significant reduction was observed in biochemical parameters and mutagenic effects of methylmercury. The study results therefore indicated that prolactin has protective effects against the toxicity of methylmercury and allowed us to suggest the continuation of research to propose prolactin in the future, as an alternative to prevent the damage caused by mercury, especially in populations that are more exposed.

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