Effect of the Size and Carbides Dispersion in the Sintering and Hardness of Samples of Stainless Steel Reinforced with NbC And TaC

Da Silva Soares,Sergio R. Gomes,Uilame Umbelino,Furukava Marciano,De Souza Carlson Pereira 한국분말야금학회 2006 한국분말야금학회 학술대회논문집 Vol.2006 No.1

The present study investigates the behavior of the sintering and hardness of stainless steel samples reinforced with NbC and TaC. Matrixes of pure stainless steel were compacted with addition of up to 3% wt NbC or TaC in a cylindrical die of steel at 700 MPa and sintered in an electrical resistance furnace under argon atmosphere. The sintered samples were characterized by density and hardness measurement, optical microscopy and scanning electron microscopy (SEM). The preliminary results show that the size and distribution of carbides influence in the sintering and hardness of the sintered samples.

Evaluation of salt and root-zone temperature stresses in leafy vegetables using hydroponics as a clean production cultivation technique in northeastern Brazil

da Silva Mairton Gomes,Gheyi Hans Raj,da Silva Lucas Lesqueves,de Souza Thaisa Teixeira,Silva Petterson Costa Conceição,Queiroz Laila de Andrade,dos Santos Thainan Sipriano,Soares Tales Miler 한국원예학회 2024 Horticulture, Environment, and Biotechnology Vol.65 No.1

Hydroponics has represented an emerging solution for regions with freshwater scarcity. Besides requiring a lower volume of water for production, this cultivation technique allows the use of brackish waters with high salinity levels. Under normal cultivation conditions (i.e., without any environmental control), plants are exposed to other abiotic stresses, such as tem perature, which can further enhance the salinity eff ect. Given the above, three experiments were conducted using a nutrient f i lm technique (NFT) hydroponic system: from April to May (autumn) with endive ( Cichorium endivia L., cv. Gigante Barbarella), from May to July (autumn/winter) with lettuce ( Lactuca sativa L., cv. Rubinela and cv. Veneranda), and from August to October (winter/spring) with chicory ( Cichorium intybus L., cv. Pão de Açúcar and cv. Radiche Todo Ano), in 2021. The trials aimed to evaluate the isolated and/or combined eff ect of salt and root-zone temperature stresses on yield, water use effi ciency, and visual quality of these vegetables. In all experiments, plants were subjected to stresses for 25 days in a randomized block design with a 2 × 4 factorial arrangement: two levels of electrical conductivity of water –ECw (0.30 and 5.50 dS m –1 for endive and chicory; 0.25 and 6.50 dS m −1 for lettuce) combined with four root-zone temperatures – RZTs (ambient-ARZT, ARZT + 2 °C, ARZT + 4 °C, and ARZT + 6 °C, corresponding to the mean temperatures of 24.72, 26.90, 28.77, and 30.73 °C for endive; 24.20, 26.00, 28.00, and 29.99 °C for lettuce; 27.12, 28.93, 31.01, and 32.86 °C for chicory). The isolated eff ects of RZT stresses or ECw levels on endive traits were observed, with leaf fresh matter losses of approxi mately 17 and 44% at higher ARZT + 6 °C (mean of 30.73 °C) and salinity (ECw 5.50 dS m –1 ), respectively. Shoot fresh matter losses of around 32 and 52% (Veneranda and Rubinela lettuces, respectively) and 65% (Radiche Todo Ano chicory) occurred only due to salt stress. The interaction aff ected the shoot fresh matter of Pão de Açúcar chicory, with approximate losses of 80% at higher ARZT + 6 °C (mean of 32.86 °C) and salt stress (ECw 5.50 dS m –1 ) than ARZT and ARZT + 2 °C and without salt stress (ECw 0.30 dS m –1 ). Despite these reductions, visual quality of plants was not depreciated. Therefore, the present study suggested cultivating leafy vegetables such as lettuce, chicory, and endive using brackish waters, even under high temperatures of nutrient solutions.

Saline extract of Portulaca elatior leaves with photoprotective and antioxidant activities does not show acute oral and dermal toxicity in mice

da Silva Suéllen Pedrosa,da Costa Clarice Barbosa Lucena,de Freitas Anderson Felipe Soares,da Silva José Dayvid Ferreira,Costa Wêndeo Kennedy,da Silva Wênio Sandoval Filho Lima,Machado Janaina Carla B 한국독성학회 2023 Toxicological Research Vol.39 No.2

The present study aimed to evaluate saline extracts from the leaves (LE) and stem (SE) of Portulaca elatior in relation to their phytochemical composition and photoprotective and antioxidant effects, as well as to evaluate the toxicity of the leaf extract. The extracts were characterized for protein concentration and phenol and flavonoid contents, as well as for thin layer chromatography (TLC) and high-performance liquid chromatography (HPLC) profiles. Total antioxidant capacity and DPPH and ABTS+ scavenging activities were determined. In the photoprotective activity assay, the sun protection factor (SPF) was calculated. The toxicity evaluation of LE included in vitro hemolytic assay and in vivo oral and dermal acute toxicity assays in Swiss mice. LE showed the highest protein, phenol, and flavonoid (8.79 mg/mL, 323.46 mg GAE/g, and 101.96 QE/g, respectively). TLC revealed the presence of flavonoids, reducing sugars, terpenes, and steroids in both extracts. In HPLC profiles, LE contained flavonoids, while SE contained flavonoids and ellagic tannins. The antioxidant activity assays showed the lowest IC50 values (34.15–413.3 μg/mL) for LE, which presented relevant SPF (> 6) at 50 and 100 μg/mL. LE demonstrated low hemolytic capacity, and no signs of intoxication were observed in mice treated orally or topically at 1000 mg/kg. However, at 2000 mg/kg, an increase in the mean corpuscular volume of erythrocytes and a reduction in lymphocytes were observed; animals treated topically with 2000 mg/kg displayed scratching behavior during the first hour of observation and showed edema and erythema that regressed after six days. In conclusion, LE did not present acute oral or dermal toxicity in Swiss mice at a dose of 1000 mg/kg and showed slight toxicity in animals treated with 2000 mg/kg.

Three-Dimensional Cell Cultures as a Research Platform in Lung Diseases and COVID-19

da Silva da Costa Felipe Allan,Soares Murilo Racy,Malagutti-Ferreira Maria José,da Silva Gustavo Ratti,Lívero Francislaine Aparecida dos Reis,Ribeiro-Paes João Tadeu 한국조직공학과 재생의학회 2021 조직공학과 재생의학 Vol.18 No.5

Background: Chronic respiratory diseases (CRD) are a major public health problem worldwide. In the current epidemiological context, CRD have received much interest when considering their correlation with greater susceptibility to SARS-Cov-2 and severe disease (COVID-19). Increasingly more studies have investigated pathophysiological interactions between CRD and COVID-19. Area covered: Animal experimentation has decisively contributed to advancing our knowledge of CRD. Considering the increase in ethical restrictions in animal experimentation, researchers must focus on new experimental alternatives. Two-dimensional (2D) cell cultures have complemented animal models and significantly contributed to advancing research in the life sciences. However, 2D cell cultures have several limitations in studies of cellular interactions. Three-dimensional (3D) cell cultures represent a new and robust platform for studying complex biological processes and are a promising alternative in regenerative and translational medicine. Expert opinion: Three-dimensional cell cultures are obtained by combining several types of cells in integrated and self-organized systems in a 3D structure. These 3D cell culture systems represent an efficient methodological approach in studies of pathophysiology and lung therapy. More recently, complex 3D culture systems, such as lung-on-a-chip, seek to mimic the physiology of a lung in vivo through a microsystem that simulates alveolar-capillary interactions and exposure to air. The present review introduces and discusses 3D lung cultures as robust platforms for studies of the pathophysiology of CRD and COVID-19 and the mechanisms that underlie interactions between CRD and COVID-19. Background: Chronic respiratory diseases (CRD) are a major public health problem worldwide. In the current epidemiological context, CRD have received much interest when considering their correlation with greater susceptibility to SARS-Cov-2 and severe disease (COVID-19). Increasingly more studies have investigated pathophysiological interactions between CRD and COVID-19. Area covered: Animal experimentation has decisively contributed to advancing our knowledge of CRD. Considering the increase in ethical restrictions in animal experimentation, researchers must focus on new experimental alternatives. Two-dimensional (2D) cell cultures have complemented animal models and significantly contributed to advancing research in the life sciences. However, 2D cell cultures have several limitations in studies of cellular interactions. Three-dimensional (3D) cell cultures represent a new and robust platform for studying complex biological processes and are a promising alternative in regenerative and translational medicine. Expert opinion: Three-dimensional cell cultures are obtained by combining several types of cells in integrated and self-organized systems in a 3D structure. These 3D cell culture systems represent an efficient methodological approach in studies of pathophysiology and lung therapy. More recently, complex 3D culture systems, such as lung-on-a-chip, seek to mimic the physiology of a lung in vivo through a microsystem that simulates alveolar-capillary interactions and exposure to air. The present review introduces and discusses 3D lung cultures as robust platforms for studies of the pathophysiology of CRD and COVID-19 and the mechanisms that underlie interactions between CRD and COVID-19.

Effects of Passiflora edulis (Yellow Passion) on Serum Lipids and Oxidative Stress Status of Wistar Rats

Maricelma da Silva Soares de Souza,Sandra Maria Barbalho,De´bora Cristina Damasceno,Marilza Vieira Cunha Rudge,Kleber Eduardo de Campos,Ana Carolina Goyos Madi,Bruno Ribeiro Coelho,Rodrigo Ce´sar Oliv 한국식품영양과학회 2012 Journal of medicinal food Vol.15 No.1

The aim of this study was to evaluate the effects of Passiflora edulis f. flavicarpa Degener (yellow passion) juice on the lipid profile and oxidative stress status of Wistar rats. Adult male Wistar rats were divided in two groups (n = 8 animals per group): the control group, which received water, and the treated group, which was given P. edulis juice (1,000 mg/kg). Both groups received by gavage treatment twice a day for 28 days. The treated group showed an increased high-density lipoproteincholesterol level and decreased low-density lipoprotein-cholesterol and free fatty acid levels compared with the control group. Levels of triglycerides and and very low-density lipoprotein-cholesterol, superoxide dismutase activity, and total glutathione concentration were not statistically different between the two groups, but the thiobarbituric acid–reactive substances concentration (indicating lipid peroxidation) decreased in the treated group. These findings suggests that P. edulis juice in the experimental conditions used showed beneficial effects on lipid profile and improved lipid peroxidation in Wistar rats.

Effect of Morinda citrifolia and Annona muricata on Erhlich Tumor Cells in Swiss Albino Mice and In Vitro Fibroblast Cells

Cleber da Silveira Torres,Francisnaira da Silva Santos,Elen Landgraf Guiguer,Adriano Cressoni de Araujo,Sandra Maria Barbalho,Patricia Cincotto dos Santos Bueno,Maricelma Silva Soares de Souza,Danilo 한국식품영양과학회 2019 Journal of medicinal food Vol.22 No.1

Morinda citrifolia (MC) and Annona muricata (AM) are popularly used for the treatment of several diseases, including cancer. Our objective was to evaluate the effects of the juice of the MC fruit, and the ethanolic extract of AM leaves on Erhlich tumor cells, in mice and in vitro fibroblastic cells. The animals were divided into G1 and G2: controls; G3: treated with AM, and G4 juice: treated with MC. The animals were subjected to intraperitoneal inoculation of 103 tumor cells and then treated with the plants. G1 and G2 received a saline solution. Cells were grown in RPMI 1640 medium, supplemented with 10% fetal bovine serum, and maintained at 37°C in 5% CO2 atmosphere. After growth, the cells were trypsinized and incubated again. Subsequently, serial dilution of extracts and juice was performed and incubated again for 48 h. We evaluated the ascites growth, the survival rate, and cytotoxicity in fibroblast cells. AM and MC did not interfere in the ascites pattern. MC, but not AM showed significance in the survival rate. Both AM and MC produced cytotoxicity activity in T3T cells. Despite advances in medicine, cancer is still one of the leading causes of death in the world and traditional medications are not always effective. The use of MC may bring beneficial effects to patients since they interfere with different mechanisms of action during carcinogenesis. However, we suggest that further investigations should be performed.

New Insights in Purinergic Therapy: Novel Antagonists for Uridine 5′-Triphosphate-Activated P2Y Receptors from Brazilian Flora

Natiele Carla da Silva Ferreira,Roˆmulo Jose´ Soares-Bezerra,Rebeca Ferreira Couto da Silveira,Clayton Menezes da Silva,Carla Santos de Oliveira,Andrea Surrage Calheiros,Taˆnia Maria Alves,Carlos Leom 한국식품영양과학회 2019 Journal of medicinal food Vol.22 No.2

P2Y2 and P2Y4 receptors are physiologically activated by uridine 5′-triphosphate (UTP) and are widely expressed in many cell types in humans. P2Y2 plays an important role in inflammation and proliferation of tumor cells, which could be attenuated with the use of antagonists. However, little is known about the physiological functions related to P2Y4, due to the lack of selective ligands for these receptors. This can be solved through the search for novel compounds with antagonistic activity. The aim of this study was to discover new potential antagonist candidates for P2Y2 and P2Y4 receptors from natural products. We applied a calcium measurement methodology to identify new antagonist candidates for these receptors. First, we established optimal conditions for the calcium assay using J774.G8, a murine macrophage cell line, which expresses functional P2Y2 and P2Y4 receptors and then, we performed the screening of plant extracts at a cutoff concentration of 50 μg/mL. ATP and ionomycin, known intracellular calcium inductors, were used to stimulate cells. The calculated EC50 were 11 μM and 103 nM, respectively. These cells also responded to the UTP stimulation with an EC50 of 1.021 μM. Screening assays were performed and a total of 100 extracts from Brazilian plants were tested. Joannesia princeps Vell. (stem) and Peixotoa A. Juss (flower and leaf) extracts stood out due to their ability to inhibit UTP-induced responses without causing cytotoxicity, and presented an IC50 of 32.32, 14.99, and 12.98 μg/mL, respectively. Collectively, our results point to the discovery of potential antagonist candidates from Brazilian flora for UTP-activated receptors.

Seminário de música brasileira na aula de português língua adicional: análise interacional da construção conjunta da aprendizagem

GabrieladaSilvaBulla ( Gabriela Da Silva Bulla ),LetíciaSoaresBortolini ( Letícia Soares Bortolini ),GrazielaHoerbeAndrighetti ( Graziela H. Andrighetti ),MargareteSchlatter ( Margarete Schlatter ) 한국포르투갈-브라질학회 2011 포르투갈-브라질 연구 Vol.8 No.2

In this paper, we investigate how institutional identity relations and the selection of learning objects can be interactionally conceived in an additional language classroom oriented to language use as social action (Clark, 1996). Informed by Ethnomethodological Conversation Analysis and Interactional Sociolinguistics, we analyse an eight-minute sequence of interaction featuring participants engaged in the accomplishment of a Portuguese-as-an-additional-language classroom activity, namely a seminar on Brazilian music, in which each student was supposed to lecture on a different musical style. In order to co-construct learning, participants orient to various identities and understandings that are built and negotiated in the course of interaction, configuring different participant frameworks. The analyses show (1) the rearrangement of the lecturer’s speech through the construction of new concepts in interaction (emergent products), and (2) the participants’ efforts to sustain the seminar frame, through the negotiation of conflicting identities of lecturer/audience, teacher/student and Brazilian national/foreigner to Brazil. This paper evidences that, more than requiring the use of the additional language, pedagogical activities such as the one analysed are opportunities for the participants to negotiate identities and modes of participation, define relevant learning objects in the course of interaction, and locally deal with the unexpected.

Are home-based exercises effective to reduce blood pressure in hypertensive adults? A systematic review

Gabriel Dias Rodrigues,Ligia Soares Lima,Nicole Cristine Simões da Silva,Paula Gomes Lopes Telles,Teresa Mell da Mota Silva Rocha,Victor Quintella de Aragão Porto,Viviane Veloso Cardoso,Pedro Paulo da 대한고혈압학회 2022 Clinical Hypertension Vol.28 No.-

Sedentarism and chronic non-communicable diseases have been a worldwide health problem that is drastically exacerbated by the COVID-19 pandemic social impacts. Home-based exercises are widely encouraged during social isolation to counterbalance the physical inactive impacts. Although, in the context of hypertension, are home-based exercises effective in blood pressure controlling? Our objective is to conduct a systematic review of high-quality controlled trials comparing the possible effects of different types of home-based exercises in hypertensive patients. The literature search was carried out in three scientific databases: Medline, Europe PMC, and Lilacs. Articles were included following three criteria: analyzing the effect of home-based exercise programs on blood pressure in treated and untreated hypertensive patients; exercises must perform at home and on the frequency, intensity, time, and type (FITT) principle, and the articles were published in English. From the qualitative analysis of 27 original trials screened through 451 identified studies, the main results are the following: 1) both endurance, isometric strength, and respiratory home-based exercise programs were efficient to decrease blood pressure in hypertensive patients; 2) differences in methodological approaches regarding FITT components, distinct blood pressure values at baseline and specific underlying mechanisms must be considered as a potential bias of each home-based interventions. In conclusion, endurance, isometric strength, and breathing home-based programs seems to be effective to reduce blood pressure in hypertensive patients. However, further randomized controlled trials and mechanistic studies must be performing to guide evidence-based recommendations of home-based exercises as antihypertensive therapy.

Quality of biosafety guidelines for dental clinical practice throughout the world in the early COVID-19 pandemic: a systematic review

Soares Renata Cristina,Rocha Juliana Schaia,da Rosa Saulo Vinicius,Gonçalves Jéssica Rodrigues da Silva Noll,Perlas Condori Priscilla Lesly,Ribeiro Ana Elisa,Moysés Samuel Jorge,Baldani Márcia 한국역학회 2021 Epidemiology and Health Vol.43 No.-

OBJECTIVES: To conduct a systematic review of coronavirus disease 2019 (COVID-19)-related biosafety guidelines for dental clinical practice in the early stage of the pandemic, focusing on quality assessment. METHODS: Electronic (via PubMed, Scopus, Web of Science, Latin American and Caribbean Health Sciences Literature database, Brazilian Library in Dentistry, and Cochrane Library) and gray literature searches were performed for documents published up to May 12, 2020. Guidelines updated until April 17, 2021 were identified. Documents were included as guidelines if they (1) consisted of a set of statements, directions, or principles presenting current or future rules or policy; (2) were developed by government agencies, institutions, organizations, or expert panels; and (3) were related to the general conduct of health care activities rather a particular condition. Two researchers, using the Appraisal of Guidelines for Research & Evaluation II, independently extracted the recommendations and evaluated the quality of the guidelines. RESULTS: Twenty-seven documents from 19 countries were included in the review. These documents presented 122 recommendations related to (1) professional biosafety; (2) patients’/companions’ safety; (3) the organization and biosafety of the physical dental facility environment; and (4) the work process in dental care. Overall, the scientific quality of the guidelines was considered low. Some recommendations presented in these guidelines would require further research to establish their effectiveness. CONCLUSIONS: We found a wide variety of biosafety guidelines for dental practice regarding COVID-19