Leukemias are among the most prevalent types of cancer worldwide. Bone marrow mesenchymal stem cells (MSCs) participate in the development of a suitable niche for hematopoietic stem cells, and are ...involved in the development of diseases such as leukemias, to a yet unknown extent. Here we described the effect of secretome of bone marrow MSCs obtained from healthy donors and from patients with acute myeloid leukemia (AML) on leukemic cell lineages, sensitive (K562) or resistant (K562-Lucena) to chemotherapy drugs. Cell proliferation, viability and death were evaluated, together with cell cycle, cytokine production and gene expression of ABC transporters and cyclins. The secretome of healthy MSCs decreased proliferation and viability of both K562 and K562-Lucena cells; moreover, an increase in apoptosis and necrosis rates was observed, together with the activation of caspase 3/7, cell cycle arrest in G0/G1 phase and changes in expression of several ABC proteins and cyclins D1 and D2. These effects were not observed using the secretome of MSCs derived from AML patients. In conclusion, the secretome of healthy MSCs have the capacity to inhibit the development of leukemia cells, at least in the studied conditions. However, MSCs from AML patients seem to have lost this capacity, and could therefore contribute to the development of leukemia.
Eugenia brejoensis
Mazine (Myrtaceae) is source of an essential oil (EbEO) with anti-infective activities against
Staphylococcus aureus
. This study evaluated the antimicrobial and anti-inflammatory ...potentials of EbEO in
S. aureus
-infected skin wounds. The excisional lesions (64 mm
2
) were induced on Swiss mice back (6 to 8-week-old) that were allocated into 3 groups (
n = 12
): 1) non-infected wounds (CON); 2) wounds infected with
S. aureus
ATCC 6538 (Sa); 3)
S. aureus
-infected wounds and treated with EbEO (Sa + EbEO). The infected groups received approximately 10
4
CFU/wound. The animals were treated with EbEO (10 µg/wound/day) or vehicle from the 1-day post-infection (dpi) until the 10th dpi. The clinical parameters (wound area, presence of exudate, edema intensity, etc.) were daily analyzed. The levels of inflammatory mediators (cytokines, nitric oxide, VEGF) and bacterial load were measured at the cutaneous tissue at 4th dpi and 10th dpi. Topical application of EbEO accelerated wound contraction with an average contraction of 83.48 ± 11.27 % of the lesion area until 6th dpi. In this period, the rates of lesion contraction were 54.28 ± 5.57% and 34.5 ± 2.67% for CON and Sa groups, respectively. The positive effects of EbEO on wound contraction were associated with significantly (
p
< 0.05) reduction on bacterial load and the release of inflammatory mediators (IL-6, IL-17A, TNF-α, NO and VEGF). Taken together, these data confirm the antimicrobial potential of EbEO and provide insights into its anti-inflammatory effects, making this essential oil an interesting candidate for the development of new therapeutic alternatives for infected cutaneous wounds.
Resumo: Destacamos resultados de uma pesquisa que buscou compreender as contribuições para a formação continuada de professores dos anos iniciais do Ensino Fundamental, a partir de seu engajamento em ...uma ação formativa voltada ao uso do software GeoGebra no ensino de geometria, em uma escola localizada em Minas Gerais. Utilizando a metodologia da pesquisa-ação, os dados foram produzidos a partir da observação participante, utilizando-se dos instrumentos caderno de campo, videogravações das etapas de planejamento e desenvolvimento de atividades e entrevistas semiestruturadas. Para análise e organização dos dados, utilizamos a análise de conteúdo categorial. Os resultados indicam que, a partir da prática formativa, os saberes docentes foram moldados, ampliando dessa maneira, os saberes da disciplina, da experiência social e das relações pessoais, associando teoria e prática, nesse saber-fazer. Destacamos ainda, evidências de que essa ampliação e mobilização de saberes favoreceu a incorporação do GeoGebra no repertório didático dos participantes.
Abstract: This paper discusses results of qualitative research that aim to explain the contributions to in-service teacher education at elementary school according to their engagement in practice using GeoGebra to teach geometry in Minas Gerais State, Brazil. We have used action-research methodology. The data were collected through participant observation methods. Also, we have used as instruments a research journal, audio and video recordings of the teacher education program, and semi-structured interviews with two teachers. Categorical Content Analysis was used to address the data. The results suggest that teacher knowledge is molded from their involvement with the program, thus expanding their disciplinary, experiential, and personal relationships by associating theory and practice in this know-how. We also highlight evidence that this expansion and mobilization of knowledge favored the incorporation of GeoGebra in their didactic and pedagogical repertoire.
The temperature dependence of the electrical properties of composites formed by biphasic sodium titanate and poly(o-methoxyaniline) (Na2Ti3O7/Na2Ti6O13/POMA) with different concentrations of POMA ...(0%, 1%, 10%, 15%, 35% and 50%) in the ceramic matrix was determined from measurements of complex impedance. The structural details were studied by means of X-ray diffraction, confirming the formation of the Na2Ti3O7/Na2Ti6O13/POMA composites. The displacement of the (200) reflection from 2θ = 10.45° to 11.15° in the composites with 10 and 15% of POMA suggested the partial replacement of H+ for Na+ in the Na2Ti3O7 structure. The thermal properties were investigated by Thermogravimetry and Differential Thermal Analysis. The Thermogravimetry curves of the composites with POMA content of 1, 10 and 15% presented profiles similar to that of pure sodium titanate sample. The composites with 35 and 50% of POMA showed a process at temperatures around 60–70 °C, which was associated with water absorbed by the polymer. The analysis of the complex impedance spectroscopy measurements revealed that the electrical resistivity of the composites in the range from 0 to 35% increased by two orders of magnitude, with different values for each concentration. This positive temperature coefficient of resistivity was less noticeable in the composite with highest POMA mass content (50%). The rapid increase in resistivity caused an increase in the relaxation time calculated from the time domain. The electrical response of the 50% of POMA compound changes in relation to what was observed in the other compounds, which suggests that there is a saturation limit in the increase in resistivity with POMA content.
To investigate the effect of an exercise-based cardiac rehabilitation program on the quality of life (QoL) of patients with chronic Chagas cardiomyopathy (CCC). PEACH study was a single-center, ...superiority randomized clinical trial of exercise training versus no exercise (control). The sample comprised Chagas disease patients with CCC, left ventricular ejection fraction < 45%, without or with HF symptoms (CCC stages B2 or C, respectively). QoL was assessed at baseline, after three months, and at the end of six months of follow-up using the SF-36 questionnaire. Patients randomized for the exercise group (n = 15) performed exercise training (aerobic, strength and stretching exercises) for 60 min, three times a week, during six months. Patients in the control group (n = 15) were not provided with a formal exercise prescription. Both groups received identical nutritional and pharmaceutical counseling during the study. Longitudinal analysis of the effects of exercise training on QoL, considering the interaction term (group × time) to estimate the rate of changes between groups in the outcomes (represented as beta coefficient), was performed using linear mixed models. Models were fitted adjusting for each respective baseline QoL value. There were significant improvements in physical functioning (β = + 10.7; p = 0.02), role limitations due to physical problems (β = + 25.0; p = 0.01), and social functioning (β = + 19.2; p < 0.01) scales during the first three months in the exercise compared to the control group. No significant differences were observed between groups after six months. Exercise-based cardiac rehabilitation provided short-term improvements in the physical and mental aspects of QoL of patients with CCC.Trial registration: ClinicalTrials.gov Identifier: NCT02517632; August 7, 2015.
A new hybrid material was created by blending sodium titanate ceramics (Na
2
Ti
3
O
7
/Na
2
Ti
6
O
13
) with a polyvinyl alcohol (PVA) matrix, resulting in enhanced semiconductive characteristics. ...The synthesis process involved intense ultrasonic treatment and subsequent heat treatment at 900 °C. Utilizing a solvent casting method, Na
2
Ti
3
O
7
/Na
2
Ti
6
O
13
/PVA composites were fabricated. Raman spectra confirmed the presence of PVA chains and distinctive bands of sodium titanates. Elemental analysis verified the existence of Na and Ti in both composites. Morphological observations revealed the formation of irregular agglomerates upon introducing sodium titanates into the PVA structure, leading to a rise in the average surface roughness (Ra) from ~ 1.5 to 7.9 nm post-incorporation of heated Na
2
Ti
3
O
7
/Na
2
Ti
6
O
13
. Differences in morphology between samples loaded with unheated and heated Na
2
Ti
3
O
7
/Na
2
Ti
6
O
13
suggested a more effective particle incorporation into the polymeric matrix after heat treatment. Electrical measurements indicated that the composite loaded with unheated Na
2
Ti
3
O
7
/Na
2
Ti
6
O
13
exhibited the lowest electrical resistance (10
5
Ω) and a relaxation time of 3.16 × 10
− 5
s. These results demonstrate that the inclusion of sodium titanate ceramics enhances the semiconductive properties of the PVA matrix. This finding highlights the potential of this material for various electronic applications, including components for solid-state batteries.
We hypothesize that by simulating the natural priming in seeds of a species that forms transient seed banks it is possible to clarify molecular aspects of germination that lead to the recruitment of ...seedlings when the next rainy season begins. We used seeds of Solanum lycocarpum as a biological model. Our findings support the idea that the increment of seed germination kinetics when the rainy season returns is mainly based on the metabolism and embryonic growth, and that the hydropriming, at the end of seed dispersion, increases the germination window time of these seeds by mainly increasing the degradation of galactomannan of the cell wall. This can improve the energy supply (based on carbon metabolism) for seedling growth in post-germination, which improves the seedling's survival chances. From these findings, we promote a hypothetical model about how the priming at the end of the rainy season acts on mRNA synthesis in the germination of seeds from transient banks and the consequence of this priming at the beginning of the following rainy season. This model predicts that besides the Gibberellin and Abscisic Acid balance (content and sensitivity), Auxin would be a key component for the seed-seedling transition in Neotropical areas. Seed collection was performed under authorization number SISGEN AB0EB45.
Plant immune response is associated with a large-scale transcriptional reprogramming, which is regulated by numerous transcription regulators such as the Elongator complex. Elongator is a ...multitasking protein complex involved in diverse cellular processes, including histone modification, DNA methylation, and tRNA modification. In recent years, Elongator is emerging as a key regulator of plant immune responses. However, characterization of Elongator's function in plant immunity has been conducted only in the model plant Arabidopsis thaliana. It is thus unclear whether Elongator's role in plant immunity is conserved in higher plants. The objective of this study is to characterize transgenic woodland strawberry (Fragaria vesca L.) overexpressing the Arabidopsis Elongator (AtELP) genes, AtELP3 and AtELP4, and to determine whether F. vesca carries a functional Elongator complex.
Transgenic F. vesca and Arabidopsis plants were produced via Agrobacterium-mediated genetic transformation and characterized by morphology, PCR, real-time quantitative PCR, and disease resistance test. The Student's t test was used to analyze the data.
Overexpression of AtELP3 and AtELP4 in F. vesca impacts plant growth and development and confers enhanced resistance to anthracnose crown rot, powdery mildew, and angular leaf spot, which are caused by the hemibiotrophic fungal pathogen Colletotrichum gloeosporioides, the obligate biotrophic fungal pathogen Podosphaera aphanis, and the hemibiotrophic bacterial pathogen Xanthomonas fragariae, respectively. Moreover, the F. vesca genome encodes all six Elongator subunits by single-copy genes with the exception of FvELP4, which is encoded by two homologous genes, FvELP4-1 and FvELP4-2. We show that FvELP4-1 complemented the Arabidopsis Atelp4/elo1-1 mutant, indicating that FvELP4 is biologically functional.
This is the first report on overexpression of Elongator genes in plants. Our results indicate that the function of Elongator in plant immunity is most likely conserved in F. vesca and suggest that Elongator genes may hold potential for helping mitigate disease severity and reduce the use of fungicides in strawberry industry.
Combined antiretroviral therapy (cART) used to treat acquired immunodeficiency virus (HIV) induces a number of adverse effects, such as insulin resistance and dyslipidemia, which ultimately increases ...the cardiovascular risk. Advanced glycation end products (AGEs) have been implicated in the etiology of cardiovascular diseases, diabetes and other chronic diseases. It is known that physical exercise improves the lipid profile, insulin resistance and reduces the risk of cardiovascular diseases. However, the impact of physical exercise on AGE levels in HIV-infected patients has not been so far investigated. Therefore, this study compared AGEs levels in people with and without HIV and verified the effect of physical training on serum AGE levels.
Participants were initially assigned into three groups: healthy control (CTL,
= 35), physically inactive HIV-infected (In-HIV,
= 33) and physically active HIV-infected (Ac-HIV,
= 19). The In-HIV group underwent physical training for 3 months, consisting of 60-min sessions of multimodal supervised exercise (aerobic, resistance and flexibility) with moderate intensity (50-80% heart rate reserve), performed 3 times/week. AGEs were measured in serum by fluorescence spectrometry.
At baseline, serum AGEs fluorescence level was significantly higher in inactive HIV-patients when compared to controls or active HIV-patients (In-HIV: 0.93 ± 0.08 vs. controls: 0.68 ± 0.13 and Ac-HIV: 0.59 ± 0.04 A.U.;
< 0.001). Triglycerides were also higher in In-HIV than CTL (182.8 ± 102 vs. 132.8 ± 52.3 mg/dL;
< 0.05). Waist circumference was lower in Ac-HIV, compared to In-HIV and controls (83.9 ± 10.4 vs. 92.9 ± 13.5 and 98.3 ± 12.4, respectively;
< 0.05). Body mass, fasting blood glucose, LDL, HDL, and total cholesterol were similar between groups. After training, AGE levels decreased (Baseline: 0.93 ± 0.08 vs. 3 months follow-up: 0.59 ± 0.04 AU;
< 0.001), no further difference being detected vs. CTL or Ac-HIV. Conclusion: HIV-infected patients under cART exhibited elevated AGEs levels compared to healthy individuals and physically active patients. Short-term aerobic training of moderate intensity counteracted this condition.
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