Publications by authors named "Douglas Silva"

61 Publications

Epidemiology of canine visceral leishmaniasis in a vulnerable region in Brazil.

Rev Bras Parasitol Vet 2021 6;30(3):e009921. Epub 2021 Sep 6.

Laboratório de Imunologia, Departamento de Clínica, Cirurgia e Reprodução Animal, Universidade Estadual Paulista - UNESP, Campus Araçatuba, Araçatuba, SP, Brasil.

Visceral leishmaniasis (VL) is a neglected and endemic zoonosis that occurs throughout Brazil; nevertheless, few studies have focused on the early detection of the disease. The municipality of Ourinhos is a non-receptive, silent and vulnerable area for VL, where the seroprevalence of this disease has so far not been investigated. The present study aimed to determine the seroprevalence of canine VL in Ourinhos-SP, and to identify the presence of risk factors. Blood samples were obtained from 604 dogs during a rabies vaccination campaign together with application of a socioeconomic questionnaire, environmental and animal characteristics and tutor's knowledge about the disease. The samples were subjected to indirect ELISA and new samples were collected from reactive and suspect animals, including whole blood and lymph node aspiration evaluated by parasitological method, complete blood count and PCR. No animal was diagnosed as positive based on the combination of direct and indirect tests and the tutors' answers indicated little knowledge about leishmaniasis, being often confused with other diseases transmitted by arthropods; hence, according to the proposed methods, the presence of canine leishmaniasis in the city of Ourinhos was not confirmed and health education campaigns about the disease should be carried out.
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http://dx.doi.org/10.1590/S1984-29612021075DOI Listing
September 2021

Environmentally Friendly, High-Performance Fire Retardant Made from Cellulose and Graphite.

Polymers (Basel) 2021 Jul 22;13(15). Epub 2021 Jul 22.

Galembetech Consultores e Tecnologia Ltda., Campinas 13080-661, Brazil.

Many materials and additives perform well as fire retardants and suppressants, but there is an ever-growing list of unfulfilled demands requiring new developments. This work explores the outstanding dispersant and adhesive performances of cellulose to create a new effective fire-retardant: exfoliated and reassembled graphite (ERG). This is a new 2D polyfunctional material formed by drying aqueous dispersions of graphite and cellulose on wood, canvas, and other lignocellulosic materials, thus producing adherent layers that reduce the damage caused by a flame to the substrates. Visual observation, thermal images and surface temperature measurements reveal fast heat transfer away from the flamed spots, suppressing flare formation. Pinewood coated with ERG underwent standard flame resistance tests in an accredited laboratory, reaching the highest possible class for combustible substrates. The fire-retardant performance of ERG derives from its thermal stability in air and from its ability to transfer heat to the environment, by conduction and radiation. This new material may thus lead a new class of flame-retardant coatings based on a hitherto unexplored mechanism for fire retardation and showing several technical advantages: the precursor dispersions are water-based, the raw materials used are commodities, and the production process can be performed on commonly used equipment with minimal waste.
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http://dx.doi.org/10.3390/polym13152400DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8348208PMC
July 2021

IgG Antibody response to the Sputnik V vaccine: previous SARS-CoV-2 seropositive individuals might need just one vaccine dose.

Int J Infect Dis 2021 Jul 31. Epub 2021 Jul 31.

Servicio Autónomo Instituto de Biomedicina, Universidad Central de Venezuela, Caracas, Venezuela.; Universidad de Las Américas (UDLA), Quito, Ecuador. Electronic address:

Introduction: . Serology tests play an important role in assessing the immune system's response to a previous SARS-CoV-2 infection or to vaccination. In Venezuela, before and after receiving the Sputnik V vaccine, we evaluated the IgG antibody response against the nucleocapsid protein (NP) and the receptor-binding domain (RBD) of the spike protein of SARS-CoV-2 in a cohort of 86 individuals.

Methods: . Antibody responses against NP and RBD were determined with an ELISA just before, 3 weeks after the first and 6 weeks after the second dose of the vaccine.

Results: Before vaccination, 59 individuals were seronegative and the other 27 were seropositive for SARS-CoV-2 antigens NP and/or RBD. Of the seronegative cohort, 42% did not develop a measurable IgG immune response against RBD after the first vaccine dose but all (100%) had a strong IgG response after two vaccine doses. All seropositive individuals developed a strong IgG antibody response against RBD after the first vaccine dose, with antibody levels approximately 40% higher than the seronegative individuals who had received two doses. Moreover, the previously seropositive subjects showed no significant increase in IgG antibody response against RBD after the second vaccine dose.

Conclusions: We demonstrated that two dose of the Sputnik V vaccine triggers antibody response in all individuals of this study. The second vaccine dose of Sputnik V has no impact on the IgG response for who were seropositive for SARS-CoV-2 antigens prior to vaccination.
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http://dx.doi.org/10.1016/j.ijid.2021.07.070DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8325383PMC
July 2021

Jabuticaba [ (O. Berg) Kausel] Protects Liver of Diabetic Rats Against Mitochondrial Dysfunction and Oxidative Stress Through the Modulation of SIRT3 Expression.

Front Physiol 2021 6;12:665747. Epub 2021 Jul 6.

Laboratório de Estresse Oxidativo e Antioxidantes, Instituto de Biotecnologia, Universidade de Caxias do Sul (UCS), Caxias do Sul, Brazil.

Complications generated by hyperglycemia present in diabetes mellitus (DM) have been constantly related to oxidative stress and dysfunction in the mitochondrial electron transport chain (ETC). Sirtuin 3 (SIRT3), which is present in mitochondria, is responsible for regulating several proteins involved in metabolic homeostasis and oxidative stress. Studies have suggested alterations in the expression of SIRT3 in DM. The objective of this study was to evaluate the effects of phenolic compounds in jabuticaba (), a berry native to Brazil, on the activity of mitochondrial ETC complexes, SIRT3 protein expression, and oxidative stress parameters in liver of diabetic rats induced by streptozotocin. After type 1 DM induction (streptozotocin 65 mg/kg), diabetic and healthy rats were treated with jabuticaba peel extract (JPE) by gavage (0.5 g/kg of weight) for 30 days. After treatments, those diabetic rats presented impaired activities of complexes I, II, and III of ETC along with an overexpression of SIRT3. In addition, an increase in lipid peroxidation and superoxide dismutase and catalase activities was observed in the diabetic group. The treatment with JPE was able to recover the activity of the mitochondrial complexes and reduce the expression of SIRT3. Furthermore, JPE treatment reduced oxidative damage to lipids and brought the antioxidants enzyme activities to basal levels in diabetic rats. Together, these results demonstrate that JPE can reduce oxidative stress related to DM by restoring mitochondrial complexes activity and regulating SIRT3 expression. Thus, JPE could become an alternative to reduce the development of complications related to DM.
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http://dx.doi.org/10.3389/fphys.2021.665747DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8290295PMC
July 2021

Peer education: youth protagonism in a preventive approach to alcohol and other drugs.

Cien Saude Colet 2021 Jul 2;26(7):2759-2768. Epub 2021 Apr 2.

Diretoria Regional de Brasília, Fundação Oswaldo Cruz. Campus Universitário Darcy Ribeiro, Asa Norte. 70750540 Brasília DF Brasil.

This article describes the experience of the course in Health and Safety at School, which prepared young people to spread knowledge on prevention of alcohol and other drugs, using the peer education methodology. The participants were sixty 15 to 19 year-old upper secondary school students from 8 public schools in the Federal District. The activity was structured into 8 modules, with each module consisting of a meeting to discuss content, followed by field work at the schools, where students trained their colleagues and passed on information to them; and, lastly, a further meeting for the students to give feedback on their experience in the field. All activities were recorded in field diaries, photographs, and reports, providing input to this experience report. Finally, a student forum was held at which the young people presented projects to be carried out at the schools. The peer education experience enabled the young people to take the lead in their school community and territory, and acknowledged the value of sharing among people with similar experiences. It thus favoured the development of critical, artistically potent strategies for preventive action directed to adolescents in situations of social vulnerability and fostered health promotion in the school.
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http://dx.doi.org/10.1590/1413-81232021267.07322021DOI Listing
July 2021

Sintocalmy, a Passiflora incarnata Based Herbal, Attenuates Morphine Withdrawal in Mice.

Neurochem Res 2021 May 5;46(5):1092-1100. Epub 2021 Feb 5.

Programa de Pós-Graduação em Ciências Biológicas - Neurociências, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil.

Chronic opioid use changes brain chemistry in areas related to reward processes, memory, decision-making, and addiction. Both neurons and astrocytes are affected, ultimately leading to dependence. Passiflora incarnata L. (Passifloraceae) is the basis of frequently used herbals to manage anxiety and insomnia, with proven central nervous system depressant effects. Anti-addiction properties of P. incarnata have been reported. The aim of this study was to investigate the effect of a commercial extract of Passiflora incarnata (Sintocalmy®, Aché Laboratory) in the naloxone-induced jumping mice model of morphine withdrawal. In addition, glial fibrillary acidic protein (GFAP) and S100 calcium-binding protein B (S100B) levels were assessed in the frontal cortex and hippocampus, and DNA damage was verified on blood cells. In order to improve solubilization a Sintocalmy methanol extract (SME) was used. SME is mainly composed by flavonoids isovitexin and vitexin. The effects of SME 50, 100 and 200 mg/kg (i.p.) were evaluated in the naloxone-induced withdrawal syndrome in mice. SME 50 and SME 100 mg/kg decreased naloxone-induced jumping in morphine-dependent mice without reducing locomotor activity. No alterations were found in GFAP levels, however SME 50 mg/kg prevented the S100B increase in the frontal cortex and DNA damage. This study shows anti-addiction effects for a commercial standardized extract of P. incarnata and suggests the relevance of proper clinical assessment.
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http://dx.doi.org/10.1007/s11064-021-03237-wDOI Listing
May 2021

The Prevalence of Abdominal Adiposity among Primary Health Care Physicians in Bahia, Brazil: An Epidemiological Study.

Int J Environ Res Public Health 2021 01 22;18(3). Epub 2021 Jan 22.

School of Nursing, State University of Rio de Janeiro (UERJ), Rio de Janeiro, RJ 20551-030, Brazil.

Background: Labor activities are demanding for workers and can induce occupational stress. Primary health care (PHC) workers have faced problems that can lead to the development of stress and abdominal obesity. The aim of this study was to estimate the prevalence of abdominal adiposity among primary health care physicians in the metropolitan mesoregion of Salvador, Bahia.

Methods: This is a cross-sectional study conducted with physicians from the family health units (FHUs) of the metropolitan mesoregion of Salvador, Bahia, Brazil. The number of FHUs corresponded to 41 teams (52 physicians). Anamnesis was performed and a questionnaire was applied. The clinical examination consisted of measuring waist circumference (WC), blood pressure levels (BP), and body mass index (BMI), as well as examining for acanthosis nigricans. Blood samples were collected for biochemical dosages. The data obtained were analyzed by SPSS version 22.0.

Results: The sample included 41 physicians (response rate: 78.8%), of which 18 were women (44.0%). The percentage of overweight participants represented by BMI was 31.7%. The hypertriglyceridemia prevalence was 29.2%. HDL-c was low in 48.7% of the participants. The waist circumference measurement revealed a prevalence of abdominal adiposity of 38.8% (women) and 34.8% (men).

Conclusions: Medical professionals in PHC are more susceptible to having higher abdominal adiposity, especially female physicians.
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http://dx.doi.org/10.3390/ijerph18030957DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7908549PMC
January 2021

Effect of initial pH and substrate concentration on the lactic acid production from cassava wastewater fermentation by an enriched culture of acidogenic microorganisms.

Water Environ Res 2020 Oct 18. Epub 2020 Oct 18.

School of Agricultural Engineering, State University of Campinas, Campinas, Brazil.

Recently, cassava processing wastewater has been considered an alternative substrate for lactic acid production due to its appreciable carbohydrate levels. The authors carried out different batch reactor trials aiming to favor the production of lactic acid through the fermentation of non-sterilized cassava wastewater by an enriched culture of acidogenic microorganisms. To this end, the impact of different initial pHs (4.5, 5.0, 5.7, 6.5, and 7.0) and different initial substrate concentrations (10, 15.8, 30, 44.2, and 50 g/L) in terms of glucose on lactic acid production yield (Y) was evaluated by applying the design of experiment (DoE) known as central composite rotatable design (CCRD). The highest rate of lactic acid production (40 g/L) occurred with an initial pH of 6.5 and an initial substrate concentration of 50 g/L. The maximum yield was higher in trials T1, T2, T4, T5, and T8, reaching values of 0.80, 0.62, 0.60, 0.96, and 0.70 g/g, respectively. The maximum lactic acid productivity (P), of 0.60 and 0.73 g L  hr , was observed in trials T5 and T8, respectively. The enriched culture of acidogenic microorganisms was shown to favor the production of lactic acid, since the production of other acids, such as acetic and propionic acid, did not exceed 3.5 and 4.5 g/L, respectively. PRACTITIONER POINTS: Cassava wastewater presented potential to lactic acid production. The CCRD showed that highest lactic acid concentrations (40 g/L). The adoption of cassava wastewater or manipueira as a substrate resulted in important information on the tendency to obtain value-added products such as lactic acid.
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http://dx.doi.org/10.1002/wer.1467DOI Listing
October 2020

Burnout syndrome and metabolic syndrome: a cross-sectional population-based study.

Arch Environ Occup Health 2021 1;76(5):266-274. Epub 2020 Oct 1.

School of Medicine, Health Sciences Postgraduate Program, Federal University of Bahia, Salvador, Brazil.

In the population of Primary Health Care Nursing (PHC) professionals, the association between Burnout Syndrome (BS) and Metabolic Syndrome (MS) has not been investigated. The objective was to evaluate the association between BS and MS among PHC Nursing Professionals. A cross-sectional, multicenter, population-based study was conducted in the state of Bahia, Brazil, with 1,125 professionals. The prevalence of BS and MS corresponded to 18.3% and 24.4%, respectively. The prevalence in women of BS was 16.4% and of MS 23.7%, in men 31.6% for BS and 29.4% for MS. Men with BS are 3.23 times more likely to develop MS, and women 1.48 times more. BS was associated between men and women and exhibited a good discriminatory predictive power.
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http://dx.doi.org/10.1080/19338244.2020.1819186DOI Listing
August 2021

A multibiomarker approach in the caged neotropical fish to assess the environment health in a river of central Brazilian Cerrado.

Sci Total Environ 2021 Jan 19;751:141632. Epub 2020 Aug 19.

Laboratory of Environmental Biotechnology and Ecotoxicology, Institute of Tropical Pathology and Public Health, Federal University of Goiás, Goiania, Goiás, Brazil. Electronic address:

Water safety is a world-wide concern and several efforts have been made in order to ensure the conservation of aquatic ecosystems. Water quality monitoring must be performed with an integrated approach using biomonitor organisms allied to water parameters. Nonetheless, very few studies have focused on biomarker responses in neotropical fish, especially in the freshwater ecosystem of Brazilian Cerrado savanna. In present study, the active biomonitoring of the João Leite river (central Brazilian Cerrado river) was performed through the evaluation of biomarker responses in caged Astyanax lacustris in combination with land use classification and analysis of water parameters. Caged fish were exposed for seven days at four sites along the river and two control groups were kept in a tank under controlled conditions. Results showed that pasture was the predominant land use in the João Leite river basin (54.07%), followed by natural vegetation (34.92%) and other kind of land use (11.01%). Water analyses showed metal concentrations (Mn and Fe) above the maximum allowed by Brazilian regulation, with particularly higher concentrations at Site 2 (near to pasture area). Biomarker responses did not show significant differences for somatic and mutagenic biomarkers between sites. However, the comet assay showed high DNA damage at Sites 2 and 3, indicating genotoxic effects in caged fish at pasture areas. Histopathological analysis showed highest frequency of leukocyte infiltration in liver of fish from Site 2, confirming the ecotoxic effects on A. lacustris in streams impacted by grazing activities. DNA damage and leukocyte infiltration in fish hepatic tissues were sensitive biomarkers in the neotropical fish A. lacustris to assess the environment health of the Cerrado river. These results showed the importance of using a multibiomarker approach in environmental risk assessment, especially in areas more at risk from anthropogenic pollution.
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http://dx.doi.org/10.1016/j.scitotenv.2020.141632DOI Listing
January 2021

Jabuticaba (Plinia trunciflora (O. Berg) Kausel) improved the lipid profile and immune system and reduced oxidative stress in streptozotocin-induced diabetic rats.

J Food Biochem 2020 09 21;44(9):e13383. Epub 2020 Jul 21.

Laboratório de Estresse Oxidativo e Antioxidantes, Instituto de Biotecnologia, Universidade de Caxias do Sul (UCS), Caxias do Sul, Brazil.

The aim of this study was evaluating the effects of jabuticaba aqueous extract (JPE - 0.5 g/kg) on serum lipid levels, immune system, and oxidative stress parameters of streptozotocin-induced diabetic rats. Administration of JPE for 30 days, by gavage, was able to reduce serum levels of total cholesterol, non-high density lipoprotein (HDL) cholesterol, and triglycerides in diabetic rats. The HDL cholesterol levels increased in both diabetic and healthy rats after JPE treatment. Total leukocyte and lymphocyte counts reduced in diabetic rats, and JPE treatment prevented these diabetes mellitus (DM)-induced changes in the immune system. In addition, the induction of DM also led to dysregulation in the activity of superoxide dismutase and catalase antioxidant enzymes as well as an increase in oxidative stress markers. Treatments with JPE reduced oxidative stress and modulated antioxidant enzyme activities. These data demonstrate the potential of JPE as an adjuvant treatment option for diabetic patients. PRACTICAL APPLICATIONS: Considering that it is very common to observe dyslipidemia in diabetic patients and that these alterations, combined with the increased oxidative stress levels, also common in these patients, can lead to the development of cardiovascular diseases, JPE would be an alternative treatment adjunct to reduce these risks. In addition, although more studies are needed, JPE has the potential to improve the count of total lymphocytes and leukocytes, which could assist in improving the immune response of these patients, who also commonly have a higher risk of infectious diseases. Thus, JPE could be used by these patients, in combination with conventional treatment, in the form of a nutraceutical rich in phenolic compounds.
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http://dx.doi.org/10.1111/jfbc.13383DOI Listing
September 2020

Revealing the Role of Tin(IV) Halides in the Anisotropic Growth of CsPbX Perovskite Nanoplates.

Angew Chem Int Ed Engl 2020 Jul 7;59(28):11501-11509. Epub 2020 May 7.

Instituto de Química, Universidade Estadual de Campinas, PO Box 6154, 13083-970, Campinas, São Paulo, Brazil.

CsPbX perovskite nanoplates (PNPLs) were formed in a synthesis driven by SnX (X=Cl, Br, I) salts. The role played by these hard Lewis acids in directing PNPL formation is addressed. Sn disturbs the acid-base equilibrium of the system, increasing the protonation rate of oleylamine and inducing anisotropic growth of nanocrystals. Sn cations influence the reaction dynamics owing to complexation with oleylamine molecules. By monitoring the photoluminescence excitation and photoluminescence (PL) spectra of the PNPLs grown at different temperatures, the influence of the thickness on their optical properties is mapped. Time-resolved and spectrally resolved PL for colloidal dispersions with different optical densities reveals that the dependence of the overall PL lifetime on the emission wavelength do not originate from energy transfer between PNPLs but from the contribution of PNPLs with distinct thickness, indicating that thicker PNPLs exhibit longer PL lifetimes.
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http://dx.doi.org/10.1002/anie.202002641DOI Listing
July 2020

Effect of freezing/irradiation/thawing processes and subsequent aging on tenderness, color, and oxidative properties of beef.

Meat Sci 2020 May 3;163:108078. Epub 2020 Feb 3.

Departamento de Ciência dos Alimentos, Universidade Federal de Lavras, P.O. Box 3037, Lavras, Minas Gerais 37200-000, Brazil. Electronic address:

This study evaluated the use of gamma irradiation (3, 6 and 9 kGy) in frozen vacuum-packed beef and subsequent thawing and aging for up to 14 days. The effects on tenderness, color, and oxidative properties were determined and compared to non-irradiated controls for frozen/thawed and chilled vacuum-packed beef. The combined irradiation and freezing/thawing processes increased total exudate loss and reduced the meat water-holding capacity, regardless of the dose used. Myofibrillar fragmentation was favored by the freezing/thawing processes and negatively affected by irradiation. Lower shear force values were observed in the non-irradiated frozen/thawed samples. Frozen samples irradiated at 9 kGy had a higher percentage of soluble collagen, lipid peroxidation, and a more reddish color tone. The meat reducing capacity and oxygen consumption were reduced by freezing and further by irradiation, which also included accumulation of metmyoglobin. It was concluded that irradiation of frozen meat and its subsequent thawing and aging does not confer any additional advantages for beef technological quality.
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http://dx.doi.org/10.1016/j.meatsci.2020.108078DOI Listing
May 2020

Antifungal and Antivirulence Activities of Hydroalcoholic Extract and Fractions of Leaves against Vaginal Isolates of Species.

Pathogens 2020 Jan 28;9(2). Epub 2020 Jan 28.

Laboratório de Microbiologia Aplicada, Programa de Biologia Microbiana, Universidade Ceuma, 65075-120 São Luís, Ma, Brazil.

Vulvovaginal candidiasis is a common fungal infection in women. In this study, hydroalcoholic extract (PiHE) and its fractions were evaluated for antifungal and antivirulence activities against vaginal species. Dichloromethane (DCMF) and ethyl acetate fractions (EAF) obtained from PiHE effectively inhibited the pathogen. Electrospray ionization mass spectrometry was used for identifying the main compounds in extracts. Minimal inhibitory and fungicidal concentrations (MIC and MFC, respectively) were determined by a broth microdilution assay. Furthermore, we evaluated the effect of the extract and fractions on the virulence properties of , and their cytotoxicity effect was determined on RAW 264.7 cells. Compounds found in extracts were flavonoid glycosides, mainly derivatives of quercetin and myricetin. Extracts showed antifungal potential, with the lowest MIC value for EAF (1.3 mg/mL) and inhibited adherence and biofilm formation. EAF disrupted 48 h biofilms with an inhibition rate of more than 90%. The extract and its fractions exhibited no cytotoxicity. The antifungal effects were attributed to the ability of these extracts to alter the mitochondrial membrane potential for the release of pro-apoptotic factors in the cytosol. In conclusion, our data suggest that PiHE and EAF could act as novel candidates for the development of new therapeutic treatments against fungal infections.
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http://dx.doi.org/10.3390/pathogens9020084DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7168675PMC
January 2020

Prevalence and Factors Associated with Burnout Syndrome among Primary Health Care Nursing Professionals: A Cross-Sectional Study.

Int J Environ Res Public Health 2020 01 11;17(2). Epub 2020 Jan 11.

Multidisciplinary Center, Federal University of Acre (UFAC), Cruzeiro do Sul 69980-000, Acre, Brazil.

The objective of the study was to evaluate the prevalence and factors associated with Burnout Syndrome (BS) in Primary Health Care (PHC) nursing professionals from the state of Bahia, Brazil. A multicentre, cross-sectional population-based study was conducted in a cluster sample among 1125 PHC Nursing professionals during the years 2017 and 2018. We used a questionnaire that included sociodemographic, labor and lifestyle variables and the Maslach Burnout Inventory scale to identify BS. The associations were evaluated using a robust Poisson regression with the hierarchical selection of the independent variables. The prevalence of BS was 18.3% and the associated factors were ethnicity (prevalence ratio (PR) = 0.62, confidence interval (CI) 95% = 0.47-0.83), residence (PR = 2.35, CI 95% = 1.79-3.09), economic situation (PR = 1.40, CI 95% = 1.06-1.86), satisfaction with current occupation (PR = 1.75, CI 95% = 1.31-2.33), (PR = 1.60, CI 95% = 1.23-2.08), rest (PR = 1.83, 95% CI = 1.41-2.37), technical resources and equipment (PR = 1.37, CI 95% = 1.06-1.77), night shift (PR = 1.49, CI 95% = 1.14-1.96), physical activity practice (PR = 1.72; CI 95% = 1.28-2.31), smoking (PR = 1.82, CI 95% = 1.35-2.45), and satisfaction with physical form (PR = 1.34, CI 95% = 1.01-179). Strategies are needed to prevent BS, with an emphasis on implementing worker health programs in the context of PHC.
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http://dx.doi.org/10.3390/ijerph17020474DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7014013PMC
January 2020

Short-Term Resistance Training Improves Cardiac Autonomic Modulation and Blood Pressure in Hypertensive Older Women: A Randomized Controlled Trial.

J Strength Cond Res 2020 Jan;34(1):37-45

Graduate Associate Program in Physical Education, Federal University of Paraiba/University of Pernambuco, João Pessoa, Paraiba, Brazil.

Oliveira-Dantas, FF, Brasileiro-Santos, MdS, Thomas, SG, Silva, AS, Silva, DC, Browne, RAV, Farias-Junior, LF, Costa, EC, and Santos, AdC. Short-term resistance training improves cardiac autonomic modulation and blood pressure in hypertensive older women: a randomized controlled trial. J Strength Cond Res 34(1): 37-45, 2020-This randomized controlled trial investigated the efficacy of short-term resistance training (RT) on cardiac autonomic modulation and peripheral hemodynamic parameters in hypertensive older women. Twenty-five hypertensive older women who were insufficiently active (64.7 ± 4.7 years) participated in this study. Subjects were randomly allocated to a 10-week RT program (2 d·wk in the first 5 weeks; 3 d·wk in the last 5 weeks) or a nonexercise control group. Linear reverse periodization was used for the RT program. Cardiac autonomic modulation, mean blood pressure (MBP), peripheral vascular resistance (PVR), and resting heart rate (RHR) were measured before and after 10 weeks. The RT group reduced cardiac sympathetic modulation (0V%; B = -6.6; 95% confidence interval [CI]: -12.9 to -0.2; p = 0.045; Cohen's d = 0.88) and showed a trend for increased parasympathetic modulation (2V%; B = 12.5; 95% CI: 0-25; p = 0.050; Cohen's d = 0.87) compared with the control group. The RT group reduced MBP (B = -8.5 mm Hg; 95% CI: -13.6 to -3.4; p = 0.001; Cohen's d = 1.27), PVR (B = -14.1 units; 95% CI: -19.9 to -8.4; p < 0.001; Cohen's d = 1.86), and RHR (B = -8.8 b·min; 95% CI: -14.3 to -3.3; p = 0.002; Cohen's d = 1.20) compared with the control group. In the RT group, the changes in 2V% patterns and low-frequency components showed a correlation with changes in MBP (r = -0.60; p = 0.032) and RHR (r = 0.75; p = 0.0003). In conclusion, 10 weeks of RT improved cardiac autonomic modulation and reduced MBP and PVR in hypertensive older women. These results reinforce the importance of RT for this population.
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http://dx.doi.org/10.1519/JSC.0000000000003182DOI Listing
January 2020

The tadpole of Physalaemus orophilus from the Atlantic rainforest of southeastern Brazil (Amphibia, Anura, Leptodactylidae).

Zootaxa 2019 Jul 4;4629(1):zootaxa.4629.1.11. Epub 2019 Jul 4.

Programa de Pós-Graduação em Manejo e Conservação de Ecossistemas Naturais e Agrários, Universidade Federal de Viçosa, Campus Florestal, Florestal, Minas Gerais, Brazil.

The neotropical genus Physalaemus Fitzinger is currently composed by 48 species (Cardozo Pereyra 2018). Recently, a phylogenetic analysis aiming to investigate the internal relationships of the genus recovered two major clades, the Physalaemus cuvieri and P. signifer clades (Lourenço et al. 2015). The following species groups were retrieved in the first clade: P. biligonigerus, P. cuvieri, P. gracilis, P. henselii, and P. olfersii groups (Lourenço et al. 2015). This proposal redefined the P. olfersii group including P. olfersii (Lichtenstein Martens), P. soaresi Izecksohn, P. maximus Feio, Pombal, Caramaschi, P. feioi Cassini, Cruz, Caramaschi and P. lateristriga (Steindachner). The authors also allocated tentatively P. orophilus Cassini, Cruz, Caramaschi, and P. insperatus Cruz, Cassini, Caramaschi in the P. olfersii group due to their morphological similarity with the other species (Cruz et al. 2008; Cassini et al. 2010). Otherwise, Physalaemus aguirrei Bokermann was not recovered nested within this group, contradicting what was suggested in a previous phenetic analysis (Nascimento et al. 2005). Members of the P. olfersii group inhabit the Atlantic rainforest and most of them have a similar advertisement calls with pulsed notes, without frequency modulation and harmonic structure (Giaretta et al. 2009; Cassini et al. 2010; Lourenço et al. 2015). Regarding their larval stage, only P. soaresi, P. maximus, and P. olfersii have their tadpoles described (Weber et al. 2005; Baêta et al. 2007; Giaretta et al. 2009). Physalaemus orophilus occurs in montane Atlantic Forest sites at the eastern slope of the Espinhaço Range in the State of Minas Gerais, southeastern Brazil (Cassini et al. 2010). Herein, we describe the tadpole of P. orophilus from Quadrilátero Ferrífero mountain region, southern limit of the Espinhaço Range and compared it to the known tadpoles of the P. olfersii group.
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http://dx.doi.org/10.11646/zootaxa.4629.1.11DOI Listing
July 2019

Materials from renewable resources: new properties and functions.

An Acad Bras Cienc 2019 21;91(4):e20181160. Epub 2019 Oct 21.

Instituto de Química, Universidade Estadual de Campinas, Rua Josué de Castro, s/n, 13083-970 Campinas, SP, Brazil.

Sustainable production requires increasing use of raw materials from renewable sources, processed under mild conditions with minimal effluent production. These requirements are satisfied by using materials derived from biomass, in synergy with food and energy production. The possibilities of biomass are continuously enlarged by new findings, as in the intrinsic nanocomposite properties of natural rubber and the amphiphile behavior of cellulose that translated into new functional materials, including high-performance, flexible and conductive non-metallic materials. Other findings are allowing a better understanding of electrostatic phenomena that play a positive role in electrostatic adhesion and cohesion of nanocomposites made from biomass products. Moreover, this should allow the development of safe electrostatic separation techniques, suitable for the fractionation of crude mixtures of biomass residues. A current study on rubber electrostatics is showing its capabilities as a transducer of mechanical energy while providing clues to understand the performance of the dielectric elastomers used in robotic self-sensing actuators.
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http://dx.doi.org/10.1590/0001-3765201920181160DOI Listing
October 2019

Imbalance between nitric oxide and superoxide anion induced by uncoupled nitric oxide synthase contributes to human melanoma development.

Int J Biochem Cell Biol 2019 10 24;115:105592. Epub 2019 Aug 24.

Department of Physiological Sciences, Santa Casa de São Paulo School of Medical Sciences, Brazil. Electronic address:

Melanoma is the most aggressive type of cutaneous tumors due to its metastatic potential and high mortality. Increased levels of reactive oxygen species, including superoxide anion (O), and the consequent installation of a pro-oxidant environment are associated with melanoma development. The enzyme nitric oxide synthase (NOS), responsible for the production of nitric oxide (NO), when uncoupled is as a source of O, for example by the absence of its cofactor tetrahydrobiopterin (BH4). Western blot analysis showed increased expression of endothelial and inducible NOS in human melanoma cells, altering the stoichiometry between NOS levels and BH4 concentration and together with decreased BH4:BH2 ratio are contributing to NOS uncoupling. The treatment of melanoma cells with exogenous BH4 increased NO concentration and decreased O levels, leading to NOS coupling, which in turn reduced cell viability, cell proliferation and the ability of melanoma cells to form melanoma spheroids. Moreover, BH4 level restoration rendered melanoma cells more sensitive to apoptosis, demonstrating the role of dysfunctional NOS in melanoma genesis.
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http://dx.doi.org/10.1016/j.biocel.2019.105592DOI Listing
October 2019

Air pollutants as a risk factor for cognitive impairment and dementia.

Cad Saude Publica 2019 08 12;35(8):e00085919. Epub 2019 Aug 12.

Departamento de Medicina Preventiva, Universidade de São Paulo, São Paulo, Brasil.

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http://dx.doi.org/10.1590/0102-311X00085919DOI Listing
August 2019

Effect of photodynamic therapy potentiated by ultrasonic chamber on decontamination of acrylic and titanium surfaces.

Photodiagnosis Photodyn Ther 2019 Sep 4;27:345-353. Epub 2019 Jul 4.

Health Science Center - Dentistry, Paraná Northern State University - UENP, Jacarezinho, PR, Brazil; Medical and Dental Institute of Phototherapy Foggiato, Jacarezinho, PR, Brazil. Electronic address:

Photodynamic Therapy (PDT) is an alternative to surface decontamination that is based on the interaction between a non-toxic photosensitizer (PS) and a light source to allow for the formation of reactive oxygen species. The objective of this study was to test a new patented device - the "Ultrasonic Photodynamic Inactivation Device" (UPID) under the patent deposit MU-BR 20.2018.00.9356-3 - for the photodynamic inactivation on contaminated acrylic plates and titanium disk. This new low cost device contains light emitting diodes (LEDs) and was built in a stainless-steel container for better light distribution. In addition, 28 waterproof red LEDs plates, with a wavelength of 660 nm were used, containing three irradiators in each plate, for which the irradiation distribution and the spectral irradiance on all 6 internal faces of this device were calculated. The effect of red LED irradiation (660 nm) methylene blue (MB) (100 μmol/L) diluted in water or 70% alcohol on three types of microorganisms: Candida albicans ATCC 10231, Staphylococcus aureus ATCC 25923 and Escherichia coli ATCC 25922. In order to estimate the effects of PDI, acrylic plates and Titanium disks were contaminated by bacterial suspensions (3 × 10 CFU/mL), then treated with a solution of MB for 30 min, followed by irradiation for 30 min (0.45 J/cm). Microbial inhibition was evaluated by counting the number of colony forming units (CFU), compared to the control group. The results showed that the UPID promoted significant reduction (p < 0.001) of the microorganism when compared with the positive control. The new device promoted an effective microbial inhibition on the surfaces tested and, thus, makes possible new studies. The perspective is that this new device may be a low-cost and non-toxic alternative to the disinfection of biomedical devices, non-critical instruments and also for use in the food industry.
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http://dx.doi.org/10.1016/j.pdpdt.2019.06.011DOI Listing
September 2019

Boron Removal from Mining and Synthetic Effluents by Electrocoagulation Using Aluminum Electrodes.

ScientificWorldJournal 2019 9;2019:3746964. Epub 2019 May 9.

Departamento de Química, Universidade Federal do Espírito Santo, 29075-910 Vitória, ES, Brazil.

The efficiency of the electrocoagulation method to remove boron from synthetic and mining effluents was investigated in this study. Different parameters were tested using boric acid solution and effluent collected from a mining company located in the city of Vitória-ES. The results showed a percentage of boron removal of over 60% for the synthetic and mining effluents, using aluminum electrodes, pH 7.5, current density of 14.82 mA cm, and supporting electrolyte of 0.200 mol L. The electrocoagulation and chemical coagulation methods were also compared, in which the percentage obtained by electrocoagulation was 56.30% higher for the mining effluent. Thus, electrocoagulation was more efficient in boron removal, especially when appropriate parameters are applied.
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http://dx.doi.org/10.1155/2019/3746964DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6532284PMC
May 2019

Conduction and Excess Charge in Silicate Glass/Air Interfaces.

Langmuir 2019 Jun 6;35(24):7703-7712. Epub 2019 Jun 6.

Institute of Chemistry , University of Campinas , Campinas 13083-970 , SP , Brazil.

The glass/air interface shows electrical properties that are unexpected for a widely used electrical insulator. The mobility of interfacial charge carriers under 80% relative humidity (RH) is 4.81 × 10 m s V, 3 orders of magnitude higher than the electrophoretic mobility of simple ions in water and less than 2 orders of magnitude lower than the electron mobility in copper metal. This allows the glass/air interface to reach the same potential as a biased contacting metal quickly. The interfacial surface resistance R increases by more than 5 orders of magnitude when the RH decreases from 80 to 2%, following an S-shaped curve with small hysteresis. Moreover, the biased surfaces store charge, as shown by Kelvin potential measurements. Applying an electric field parallel to the surface produces RH-dependent results: under low humidity, the interface behaves as expected for an ideal two-dimensional parallel-plate capacitor, while under high RH, it acquires and maintains excess negative charge, which is lost under low RH. The glass surface morphology and potential distribution change on the glass/air interface under high RH and applied potential, including the extensive elimination of nonglass contaminating particles and potential levelling. All these surprising results are explained by using a protonic-charge-transfer mechanism: mobile protons dissociated from silanol groups migrate rapidly along a field-oriented adsorbed water layer, while the matrix-bound silicate anions remain immobile. Glass may thus be classified as the ionic analogue of a topological insulator but based on structural features and charge-transfer mechanisms different from the chalcogenides that have been receiving great attention in the literature.
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http://dx.doi.org/10.1021/acs.langmuir.9b00606DOI Listing
June 2019

Production and characterization of collagenase from a new Amazonian strain.

Prep Biochem Biotechnol 2019 4;49(5):501-509. Epub 2019 Apr 4.

a Laboratory of Biotechnology and Therapeutic Innovation, University of Pernambuco-UPE , Garanhuns , PE , Brazil.

A new collagenase producing a strain of , isolated from the pollen of a bee of Amazon Region (Brazil), had its enzyme characterized and the production medium composition and culture conditions enhanced. A two-level design on three factors, namely initial medium pH, the substrate (gelatin) concentration and agitation intensity, allowed identifying the first two variables as the most significant ones, while a central composite design (CCD) was subsequently used to identify their optimal levels. Statistics highlighted maximized collagenolytic activity when substrate concentration and initial medium pH were selected at their highest levels (positive effects), whereas agitation intensity at the lowest (negative effect). Triplicate runs performed under predicted optimal conditions (pH 7.8 and 1.7% gelatin concentration) yielded a collagenolytic activity (305.39 ± 5.15 U) 4.6- to 15-fold those obtained with the preliminary design. The enzyme displayed optimum activity at 45 °C and pH 7.2, was stable over wide ranges of pH values and temperatures (7.2-11.0 and 25-50 °C, respectively) and was strongly inhibited by 10 mM phenylmethylsulphonyl fluoride. The zymogram showed two prominent bands at 50 and 76 kDa. These results are a first attempt to elucidate the features of this new collagenase, its production conditions, and possible scale-up.
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http://dx.doi.org/10.1080/10826068.2019.1587627DOI Listing
June 2019

In vitro immunotoxicological assessment of a potent microbicidal nanocomposite based on graphene oxide and silver nanoparticles.

Nanotoxicology 2019 03 19;13(2):189-203. Epub 2018 Nov 19.

a Laboratory of Solid State Chemistry , Institute of Chemistry, University of Campinas , Campinas , Brazil.

Graphene oxide (GO) and silver nanoparticles (AgNPs) can be formed into a hybrid nanomaterial, known as GOAg nanocomposite, which presents high antibacterial activity. The successful translation of this nanomaterial into medical use depends on critical information about its toxicological profile. In keeping with a Safe-by-design approach, we evaluated the immunotoxicity of GOAg using J774 and primary murine macrophages. The interaction between GOAg and macrophages was investigated with a scanning electron microscope (SEM). High-throughput technologies were employed to evaluate cell viability, apoptosis/necrosis, mitochondrial depolarization and lipid peroxidation. The inflammogenicity of nanomaterials was predicted after quantification of the cytokines IL-1β, TNF-α and IL-10 before and after stimulation with interferon-γ (IFN-γ). The ratio between CD80 and CD206 macrophage populations were also estimated. In addition, the production of nitric oxide (NO) was investigated. SEM surveys revealed the potential of GOAg to induce frustrated phagocytosis. GOAg induced a dose-dependent mitochondrial depolarization, apoptosis and lipid peroxidation to J774 macrophages. GOAg toxicity was not modified in an inflammatory microenvironment, but its toxicity was within the range of concentrations used in bacterial inactivation. GOAg did not induce primary macrophages to significantly produce inflammatory cytokines, and previous macrophage stimulation did not enhance GOAg inflammogenicity. Additionally, the pristine nanomaterials and GOAg do not shift macrophages polarization towards M1. Sublethal concentrations of GOAg did not impair macrophages NO production. Finally, we suggest options for improvement of GOAg nanocomposite in ways that may help minimize its possible adverse outcomes to human health.
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http://dx.doi.org/10.1080/17435390.2018.1537410DOI Listing
March 2019

Using microwave cooking to evaluate tenderness and its relationship to sensory analysis.

J Texture Stud 2018 12 7;49(6):612-618. Epub 2018 Oct 7.

Departamento de Ciência dos Alimentos, Universidade Federal de Lavras (UFLA), Lavras, Minas Gerais, Brazil.

This study evaluated a microwave (Mw) cooking method for determining beef toughness using the Warner-Bratzler slice shear force (WBsSF) protocol. Longissimus thoracis muscles were aged for 1, 10, 19, and 28 days at 4C. They were then either cooked on a clam-shell grill until reaching an internal temperature of 72C, in a Mw for 100 s at maximum power (Mw100) or for 140 s at 60% of maximum power (Mw60). Cooking loss and shear force (SF) values were higher in Mw samples than in grilled ones. SF assessment by grill and Mw100 were able to discriminate tenderness by aging times in the same way as the sensory panel. The SF measured in a grilled sample had higher repeatability (R = .74) and correlation with sensory scores (r = -.79) than Mw100 (R = .61; r = -.62) and Mw60 (R = .51; r = -.53). Mw100 can be considered as an appropriate alternative for the WBsSF protocol. PRACTICAL APPLICATIONS: Tenderness is the most important attribute for consumers. Many studies have evaluated tenderness in meat and different protocols for cooking. This work was intended to optimize and evaluate the use of the microwave as a cooking method for shear force determination, against a standard protocol and establish the correlation to sensory tenderness.
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http://dx.doi.org/10.1111/jtxs.12367DOI Listing
December 2018

Effect of photodynamic therapy on surface decontamination in clinical orthodontic instruments.

Photodiagnosis Photodyn Ther 2018 Dec 13;24:123-128. Epub 2018 Sep 13.

São Leopoldo Mandic Dental Research Institute, Campinas, SP, Brazil.

The objective was to develop, characterize and test a box containing light emission diode (LED), Patent Deposit MU-BR20.2017.002297-3, which was named "Photodynamic Inactivation Device" (PID) and verify if it's suitable in microbial reduction or disinfection action of solid surfaces using PID. The equipment was made in a container of polypropylene with a lid of the same material and, for a better use of irradiation the internal part was covered with a layer of reflective aluminum. In addition, sixty boards of red LED 660 nm wavelength, containing three radiators each, for which the distribution of irradiation and spectral irradiance in all of the six internal faces were calculated in this device. That way, a low cost alternative was tested over three types of microorganisms present on the human microbiota: two strains Gram-positive (Gram +), Staphylococcus aureus and Streptococcus mutans and one strain Gram-negative (Gram -), Escherichia coli, inoculated in orthodontic instruments previously autoclaved. To assess the Photodynamic Inactivation (PDI) over these bacteria, instruments were contaminated by bacterial suspensions (3 × 10⁸ CFU/mL) and ulterior treatment with a solution of 100 μmol/L of MB for 20 min, and irradiated for another 20 min (energy density of 026 J/cm²). Microbial reduction was assessed by number counting of Colony Forming Units (CFU). At the end, microbial reduction of the surface of orthodontic metal instruments was compared with the positive group of each group. Results showed that PID caused a significant reduction (p < 0.05) of the microbial charge stuck in the orthodontic instruments. Thus, the photo prototype of the drawing is appropriate for phototherapy studies, granting it´s advantageous to the low level light therapy as well as for the antimicrobial photodynamic therapy. The perspective is that PID may potentialize the dissemination of phototherapy studies for determining its proper use in health science. And, thus, propose a low cost and atoxic alternative for disinfection of biomedical appliances as non-critical instruments, allowing also for use in the food industry.
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http://dx.doi.org/10.1016/j.pdpdt.2018.09.003DOI Listing
December 2018

Effect of homogenisation speed and centrifugation on particle size analysis of beef and the relationship with shear force.

Meat Sci 2018 Sep 8;143:219-222. Epub 2018 May 8.

Centre for Red Meat and Sheep Development, NSW Department of Primary Industries, P.O. Box 129, Cowra, NSW 2794, Australia.

This study aimed to investigate the effect of homogenisation speed and centrifugation on particle size (PS) evaluation, and examine its relationship with shear force. Beef Longissimus lumborum (LL) muscle portions were randomly assigned to different ageing periods (0, 3 or 5 weeks), and tested for PS and shear force. The PS analysis was conducted at different homogenisation speeds (11,000, 16,000 and 19,000 rpm) with and without a centrifugation step prior to measurement. Samples homogenised at 11,000 rpm and not centrifuged gave PS results significantly different at each ageing time as did samples homogenised at 19,000 rpm and centrifuged. Overall samples homogenised at 11,000 rpm produced the lowest coefficient of variation for PS results. There was a significant correlation between PS and shear force across the different homogeniser speeds and centrifugation statuses. It is concluded that best practice when measuring PS in beef includes a homogeniser speed of 11,000 rpm with no centrifugation prior to measurement.
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http://dx.doi.org/10.1016/j.meatsci.2018.05.006DOI Listing
September 2018

Effect of At-home and In-office Bleaching on Marginal Microleakage in Composite Resin Restorations using Two Adhesive Systems.

J Contemp Dent Pract 2018 Mar 1;19(3):248-252. Epub 2018 Mar 1.

Department of Operative Dentistry, Universidade Luterana do Brasil, Canoas, Rio Grande do Sul, Brazil.

Aim: The aim of this study is to assess marginal microleakage of cervical cavities restored with composite resins and two different adhesive techniques subjected to at-home and in-office bleaching.

Materials And Methods: In this randomized, blind laboratory experiment, 60 bovine teeth recently extracted were collected and divided into six groups (n = 10 each group). The teeth received cervical cavity preparations (2 mm × 3 mm × 1 mm) with enamel margins. Two different adhesive systems were used (Single Bond 2 and Clearfil SE Bond), in addition to composite resin (Z250). Restored teeth received two different bleaching gels (Opalescence PF and Opalescence Boost). Teeth were thermo-cycled and analyzed under confocal laser scanning microscopy.

Results: No significant differences were observed (p > 0.05) in microleakage scores between the two groups not subjected to bleaching nor between the four groups that received bleaching treatment (p > 0.05), regardless of the gel and adhesive system employed. However, when comparing nonbleached with bleached teeth, those not subjected to bleaching showed statistically lower marginal microleakage scores (p < 0.05). Data were statistically analyzed using the Kruskal-Wallis test followed by Student-Newman-Keuls post hoc test, with significance set at 5%.

Conclusion: Marginal microleakage in composite resin restorations is influenced by the action of bleaching agents used both at-home and in-office, regardless of the adhesive system employed (total-etch or self-etch).

Clinical Significance: Both at-home and in-office bleaching agents have an influence on the adhesive interface of resin restorations, producing changes and inducing marginal leakage.
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March 2018

l-Arginine supplementation does not improve muscle function during recovery from resistance exercise.

Appl Physiol Nutr Metab 2018 Sep 15;43(9):928-936. Epub 2018 Mar 15.

Center of Research in Health Sciences, North University of Paraná (UNOPAR), Londrina, Paraná 86041-120, Brazil.

The purpose of this study was to investigate the effects of l-arginine supplementation on muscle recovery after a single session of high-intensity resistance exercise (RE). Twenty healthy young adult participants (22.8 ± 3.4 years old) were assigned to 1 of 2 groups (N = 10 per group): a placebo-supplement group or an l-arginine-supplement group. The groups completed a session of high-intensity RE (0 h) and 3 subsequent fatigue test sessions (at 24, 48, and 72 h postexercise) to assess the time course of muscle recovery. During the test sessions, we assessed the following dependent variables: number of maximum repetitions, electromyographic signal (i.e., root mean square (RMS) and median frequency (MF) slope), muscle soreness, perceived exertion, blood levels of creatine kinase (CK) and lactate, and testosterone:cortisol ratio. Number of maximum repetitions increased at 48 and 72 h postexercise in both groups (time, P < 0.05). CK levels and muscle soreness increased at 24 h postexercise and then progressively returned to baseline at 72 h post exercise in both groups (time, P < 0.05). Lactate levels increased immediately postexercise but were reduced at 24 h postexercise in both groups (time, P < 0.05). Testosterone:cortisol ratio, RMS, and MF slope remained unchanged during the recovery period in both groups (time, P > 0.05). No significant (P > 0.05) group × time interaction was found for all dependent variables during the recovery period. In conclusion, our data indicate that l-arginine supplementation does not improve muscle recovery following a high-intensity RE session in young adults.
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http://dx.doi.org/10.1139/apnm-2017-0594DOI Listing
September 2018
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